Instances not reconnecting after Jenkins restart

Plugin version is 4.2.0. If I delete the instances the plugin will delete, create, and then connect again just fine. Nothing in the agent log in UI. The following error keeps coming across in Jenkins logs after restart:

```
2020-01-08 00:51:13.014+0000 [id=79] WARNING c.g.c.g.p.p.client.ComputeClient#lambda$waitForOperationCompletion$11: Error retrieving operation.
com.google.api.client.googleapis.json.GoogleJsonResponseException: 404 Not Found
{
"code" : 404,
"errors" : [ {
"domain" : "global",
"message" : "The resource 'projects/staging-af5b7922/zones/us-east1-b/operations/operation-1576034201469-599650ebb8354-a9b61b22-436cbfa9' was not found",
"reason" : "notFound"
} ],
"message" : "The resource 'projects/staging-af5b7922/zones/us-east1-b/operations/operation-1576034201469-599650ebb8354-a9b61b22-436cbfa9' was not found"
}
at com.google.api.client.googleapis.json.GoogleJsonResponseException.from(GoogleJsonResponseException.java:150)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:113)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:40)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest$1.interceptResponse(AbstractGoogleClientRequest.java:321)
at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1056)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
at com.google.cloud.graphite.platforms.plugin.client.ComputeWrapper.getZoneOperation(ComputeWrapper.java:164)
at com.google.cloud.graphite.platforms.plugin.client.ComputeClient.getZoneOperation(ComputeClient.java:584)
at com.google.cloud.graphite.platforms.plugin.client.ComputeClient.lambda$waitForOperationCompletion$11(ComputeClient.java:673)
at org.awaitility.core.CallableCondition$ConditionEvaluationWrapper.eval(CallableCondition.java:100)
at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:201)
at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:188)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
2020-01-08 00:51:13.602+0000 [id=80] WARNING c.g.c.g.p.p.client.ComputeClient#lambda$waitForOperationCompletion$11: Error retrieving operation.
com.google.api.client.googleapis.json.GoogleJsonResponseException: 404 Not Found
{
"code" : 404,
"errors" : [ {
"domain" : "global",
"message" : "The resource 'projects/staging-af5b7922/zones/us-east1-b/operations/operation-1576033832104-59964f8b77299-3e40225f-37baaed2' was not found",
"reason" : "notFound"
} ],
"message" : "The resource 'projects/staging-af5b7922/zones/us-east1-b/operations/operation-1576033832104-59964f8b77299-3e40225f-37baaed2' was not found"
}
at com.google.api.client.googleapis.json.GoogleJsonResponseException.from(GoogleJsonResponseException.java:150)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:113)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:40)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest$1.interceptResponse(AbstractGoogleClientRequest.java:321)
at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1056)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
at com.google.cloud.graphite.platforms.plugin.client.ComputeWrapper.getZoneOperation(ComputeWrapper.java:164)
at com.google.cloud.graphite.platforms.plugin.client.ComputeClient.getZoneOperation(ComputeClient.java:584)
at com.google.cloud.graphite.platforms.plugin.client.ComputeClient.lambda$waitForOperationCompletion$11(ComputeClient.java:673)
at org.awaitility.core.CallableCondition$ConditionEvaluationWrapper.eval(CallableCondition.java:100)
at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:201)
at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:188)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
```

These operations don't exist in the GCP UI. Not sure what operations it is looking for. The timestamps in the ID are for about a month back it looks like.

Let me know what other debug information would be useful.