[JENKINS-73402] Load LogManager recorder afetr CasC loading

[Dohbedoh]

Was probably introduced by #338.

Propose to load the recorders after CasC init (see https://github.com/jenkinsci/configuration-as-code-plugin/blob/1810.v9b_c30a_249a_4c/plugin/src/main/java/io/jenkins/plugins/casc/ConfigurationAsCode.java#L337).

I thought about just always targeting the reference Jenkins.get().getLog().getRecorders() from CustomHandler#publish but wonder if that would be overkill ? We go through this for every log record.. cc @jglick I wonder WDYT about this ?

Testing done

• Start Jenkins with CasC:

jenkins:
  log:
    recorders:
    - loggers:
      - level: "ALL"
        name: "jenkins.InitReactorRunner"
      name: "reactor"

• verify that $JENKINS_HOME/logs/custom/reactor.log exists

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[jglick]

Seems OK.