JCasC - configure a hudson.security.SecurityRealm

Im trying to configure Jenkins helm chart of jenkinsci with JCasC.

this is part of my value.yml
```yaml
JCasC:
defaultConfig: true
securityRealm: |-
saml:
binding: "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
displayNameAttributeName: "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name"
emailAttributeName: "email"
groupsAttributeName: "group"
idpMetadataConfiguration:
url: ""
period: 0
maximumAuthenticationLifetime: 2073600
usernameAttributeName: "username"
usernameCaseConversion: "none"
```

Im not sure what im doing wrong but im getting this error from jenkins:

```
java.lang.IllegalArgumentException: Single entry map expected to configure a hudson.security.SecurityRealm
at io.jenkins.plugins.casc.impl.configurators.HeteroDescribableConfigurator.configureMapping(HeteroDescribableConfigurator.java:291)
at io.jenkins.plugins.casc.impl.configurators.HeteroDescribableConfigurator.preConfigure(HeteroDescribableConfigurator.java:273)
at io.jenkins.plugins.casc.impl.configurators.HeteroDescribableConfigurator.configure(HeteroDescribableConfigurator.java:83)
at io.jenkins.plugins.casc.impl.configurators.HeteroDescribableConfigurator.check(HeteroDescribableConfigurator.java:92)
at io.jenkins.plugins.casc.impl.configurators.HeteroDescribableConfigurator.check(HeteroDescribableConfigurator.java:55)
at io.jenkins.plugins.casc.BaseConfigurator.configure(BaseConfigurator.java:360)
at io.jenkins.plugins.casc.BaseConfigurator.check(BaseConfigurator.java:293)
at io.jenkins.plugins.casc.ConfigurationAsCode.lambda$checkWith$9(ConfigurationAsCode.java:803)
at io.jenkins.plugins.casc.ConfigurationAsCode.invokeWith(ConfigurationAsCode.java:737)
at io.jenkins.plugins.casc.ConfigurationAsCode.checkWith(ConfigurationAsCode.java:803)
at io.jenkins.plugins.casc.ConfigurationAsCode.configureWith(ConfigurationAsCode.java:789)
at io.jenkins.plugins.casc.ConfigurationAsCode.configureWith(ConfigurationAsCode.java:658)
at io.jenkins.plugins.casc.ConfigurationAsCode.configure(ConfigurationAsCode.java:315)
at io.jenkins.plugins.casc.ConfigurationAsCode.init(ConfigurationAsCode.java:307)
Caused: java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at hudson.init.TaskMethodFinder.invoke(TaskMethodFinder.java:109)
Caused: java.lang.Error
at hudson.init.TaskMethodFinder.invoke(TaskMethodFinder.java:115)
at hudson.init.TaskMethodFinder$TaskImpl.run(TaskMethodFinder.java:185)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:305)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:1166)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:221)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:120)
at jenkins.security.ImpersonatingExecutorService$1.run(ImpersonatingExecutorService.java:68)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused: org.jvnet.hudson.reactor.ReactorException
at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:290)
at jenkins.InitReactorRunner.run(InitReactorRunner.java:49)
at jenkins.model.Jenkins.executeReactor(Jenkins.java:1201)
at jenkins.model.Jenkins.(Jenkins.java:989)
at hudson.model.Hudson.(Hudson.java:86)
at hudson.model.Hudson.(Hudson.java:82)
at hudson.WebAppMain$3.run(WebAppMain.java:247)
Caused: hudson.util.HudsonFailedToLoad
at hudson.WebAppMain$3.run(WebAppMain.java:264)
```

I tried couple of changes but nothing is working.

anyone encounter an issue like this?

I did configure everything manually and its working fine but with JCasC it doesnt