[JENKINS-73471] Restore passing credentialsId to the GitSCM

[Dohbedoh]

Proposal to fix https://github.com/jenkinsci/bitbucket-branch-source-plugin/issues/862. Reinstore the credentialsId in the GitSCM configuration. It would also guarantee that credentials usage is still tracked. Checking down the line, GitClient still uses the authenticator credentials reference.

@yaroslavafenkin Per my understanding, the issue that SECURITY-3363 fixes was the clone link of the OAuth Authenticator at https://github.com/jenkinsci/bitbucket-branch-source-plugin/blob/886.v44cf5e4ecec5/src/main/java/com/cloudbees/jenkins/plugins/bitbucket/api/credentials/BitbucketOAuthAuthenticator.java#L48-L57 ? In which case instantiating the GitSCM with the credentialsId is fine ? I am not sure what is the scenario to validate that this does not bring back this security problem ?

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