updateGitlabCommit throws NullPointerException for proxyInterface

### Jenkins and plugins versions report

Jenkins 2.462.3
GitLab API Plugin Version 5.6.0-97.v6603a_83f8690
GitLab Plugin Version 1.8.2

### What Operating System are you using (both controller, and any agents involved in the problem)?

Jenkins running as container on an Ubuntu 22.04 gen2 Vm as a part of an AKS cluster

### Reproduction steps

- Create Jenkins Job using Gitlab plugin
- Call updateGitlabCommitStatus

### Expected Results

- updateGitlabCommitStatus runs successfully

### Actual Results

```
Error when executing success post condition:
Also: org.jenkinsci.plugins.workflow.actions.ErrorAction$ErrorId: 6951fdda-dc74-4bd3-a739-a92fc8c0c89a
java.lang.NullPointerException: RESTEASY004625: proxyInterface was null
at PluginClassLoader for gitlab-plugin//org.jboss.resteasy.client.jaxrs.internal.ClientWebTarget.proxyBuilder(ClientWebTarget.java:100)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.gitlab.api.impl.ResteasyGitLabClientBuilder.buildClient(ResteasyGitLabClientBuilder.java:151)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.gitlab.api.impl.ResteasyGitLabClientBuilder.buildClient(ResteasyGitLabClientBuilder.java:93)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.connection.GitLabConnection.getClient(GitLabConnection.java:160)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.connection.GitLabConnectionConfig.getClient(GitLabConnectionConfig.java:64)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.connection.GitLabConnectionProperty.getClient(GitLabConnectionProperty.java:78)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.connection.GitLabConnectionProperty.getClient(GitLabConnectionProperty.java:91)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.util.CommitStatusUpdater.updateCommitStatus(CommitStatusUpdater.java:54)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.util.CommitStatusUpdater.updateCommitStatus(CommitStatusUpdater.java:125)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.workflow.UpdateGitLabCommitStatusStep$UpdateGitLabCommitStatusStepExecution.run(UpdateGitLabCommitStatusStep.java:77)
at PluginClassLoader for gitlab-plugin//com.dabsquared.gitlabjenkins.workflow.UpdateGitLabCommitStatusStep$UpdateGitLabCommitStatusStepExecution.run(UpdateGitLabCommitStatusStep.java:61)
at PluginClassLoader for workflow-step-api//org.jenkinsci.plugins.workflow.steps.AbstractSynchronousStepExecution.start(AbstractSynchronousStepExecution.java:41)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.DSL.invokeStep(DSL.java:323)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.DSL.invokeMethod(DSL.java:196)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsScript.invokeMethod(CpsScript.java:124)
at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.call(PogoMetaClassSite.java:47)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.sandbox.DefaultInvoker.methodCall(DefaultInvoker.java:20)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.LoggingInvoker.methodCall(LoggingInvoker.java:117)
at updateGitlabCommit.call(updateGitlabCommit.groovy:3)
at build.call(build.groovy:67)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.delegateAndExecute(ModelInterpreter.groovy:138)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.runPostConditions(ModelInterpreter.groovy:768)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.catchRequiredContextForNode(ModelInterpreter.groovy:402)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.catchRequiredContextForNode(ModelInterpreter.groovy:400)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.runPostConditions(ModelInterpreter.groovy:767)
at com.cloudbees.groovy.cps.CpsDefaultGroovyMethods.each(CpsDefaultGroovyMethods:2125)
at com.cloudbees.groovy.cps.CpsDefaultGroovyMethods.each(CpsDefaultGroovyMethods:2110)
at com.cloudbees.groovy.cps.CpsDefaultGroovyMethods.each(CpsDefaultGroovyMethods:2151)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.runPostConditions(ModelInterpreter.groovy:757)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.executeSingleStage(ModelInterpreter.groovy:684)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:294)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.toolsBlock(ModelInterpreter.groovy:551)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.toolsBlock(ModelInterpreter.groovy:550)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:282)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withEnvBlock(ModelInterpreter.groovy:450)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withEnvBlock(ModelInterpreter.groovy:449)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:281)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withCredentialsBlock(ModelInterpreter.groovy:488)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withCredentialsBlock(ModelInterpreter.groovy:487)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:280)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.inDeclarativeAgent(ModelInterpreter.groovy:593)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.inDeclarativeAgent(ModelInterpreter.groovy:592)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:278)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.stageInput(ModelInterpreter.groovy:362)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.stageInput(ModelInterpreter.groovy:361)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:267)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.inWrappers(ModelInterpreter.groovy:625)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.inWrappers(ModelInterpreter.groovy:624)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:265)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withEnvBlock(ModelInterpreter.groovy:450)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.withEnvBlock(ModelInterpreter.groovy:449)
at org.jenkinsci.plugins.pipeline.modeldefinition.ModelInterpreter.evaluateStage(ModelInterpreter.groovy:260)
at ___cps.transform___(Native Method)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.ContinuationGroup.methodCall(ContinuationGroup.java:90)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.FunctionCallBlock$ContinuationImpl.dispatchOrArg(FunctionCallBlock.java:116)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.FunctionCallBlock$ContinuationImpl.fixArg(FunctionCallBlock.java:85)
at jdk.internal.reflect.GeneratedMethodAccessor504.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.ContinuationPtr$ContinuationImpl.receive(ContinuationPtr.java:72)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.CollectionLiteralBlock$ContinuationImpl.dispatch(CollectionLiteralBlock.java:55)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.CollectionLiteralBlock$ContinuationImpl.item(CollectionLiteralBlock.java:45)
at jdk.internal.reflect.GeneratedMethodAccessor507.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.ContinuationPtr$ContinuationImpl.receive(ContinuationPtr.java:72)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.PropertyishBlock$ContinuationImpl.get(PropertyishBlock.java:75)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.LValueBlock$GetAdapter.receive(LValueBlock.java:30)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.PropertyishBlock$ContinuationImpl.fixName(PropertyishBlock.java:65)
at jdk.internal.reflect.GeneratedMethodAccessor513.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.ContinuationPtr$ContinuationImpl.receive(ContinuationPtr.java:72)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.impl.ConstantBlock.eval(ConstantBlock.java:21)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.Next.step(Next.java:83)
at PluginClassLoader for workflow-cps//com.cloudbees.groovy.cps.Continuable.run0(Continuable.java:147)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.SandboxContinuable.access$001(SandboxContinuable.java:17)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.SandboxContinuable.run0(SandboxContinuable.java:49)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsThread.runNextChunk(CpsThread.java:180)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsThreadGroup.run(CpsThreadGroup.java:423)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:331)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:295)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService.lambda$wrap$4(CpsVmExecutorService.java:140)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at hudson.remoting.SingleLaneExecutorService$1.run(SingleLaneExecutorService.java:139)
at jenkins.util.ContextResettingExecutorService$1.run(ContextResettingExecutorService.java:28)
at jenkins.security.ImpersonatingExecutorService$1.run(ImpersonatingExecutorService.java:68)
at jenkins.util.ErrorLoggingExecutorService.lambda$wrap$0(ErrorLoggingExecutorService.java:51)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService$1.call(CpsVmExecutorService.java:53)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService$1.call(CpsVmExecutorService.java:50)
at org.codehaus.groovy.runtime.GroovyCategorySupport$ThreadCategoryInfo.use(GroovyCategorySupport.java:136)
at org.codehaus.groovy.runtime.GroovyCategorySupport.use(GroovyCategorySupport.java:275)
at PluginClassLoader for workflow-cps//org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService.lambda$categoryThreadFactory$0(CpsVmExecutorService.java:50)
at java.base/java.lang.Thread.run(Unknown Source)
```

### Anything else?

We have confirmed that Jenkins is able to reach the instance of gitlab, Also that the Configuration under `Dashboard -> Manage Jenkins -> System` is valid as well

### Are you interested in contributing a fix?

_No response_