[JENKINS-68480] Automatically select owner for GitHubAppCredentials

[LeoQuote]

• 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

This pr fix https://issues.jenkins.io/browse/JENKINS-68480 ,
like jenkinsci/github-branch-source-plugin#527 , it sets RepoOwner() context automatically , make it possible to call api when using github app credentials

[LeoQuote]

Installed plugin in my jenkins instance, it made a comment successfully

[LeoQuote]

@aaronwalker hi, do you have a moment to review and merge this pr?

Multiple dependencies have been upgraded, I believe the Jenkinsfile also needs to be upgraded , I ran the compile on my pc and it works.

[aaronwalker]

@LeoQuote looks like an issue with the CI See https://github.com/jenkinsci/pipeline-github-plugin/runs/12449680268

[LeoQuote]

@aaronwalker Thanks for your review, IMHO the error is caused by the outdated build environtment, the building system is using java 8 which is not supported in the latest jenkins server.

would you consider merging #118 to bring build environment to the latest?

[aaronwalker]

@LeoQuote I've merged PR #118 can you rebase this PR to confirm it resolves the build issues and I'll look to get the merge and released

[aaronwalker]

@LeoQuote hate to be a pain but can you squash this into a single commit

[LeoQuote]

@aaronwalker certainly, done.

[aaronwalker]

LGTM