Feature/oauth bit bucket

[NickTheDevOpsGuy]

Description

This pull request adds OAuth authentication support for Git operations performed by the Jenkins plugin.

The change enables OAuth-based credentials to be used when interacting with Git repositories, providing an alternative to traditional username/password or token-based authentication flows. This allows Jenkins environments configured with OAuth credentials to authenticate successfully during supported Git operations.

Testing done

The change was tested by configuring the plugin with OAuth authentication and executing Git operations against a repository that requires OAuth-based authentication.

Testing included:

• Verified the changed OAuth authentication code path is executed during a Git operation
• Verified authentication succeeds with valid OAuth credentials
• Verified the repository can be accessed using the configured OAuth authentication
• Verified existing Git authentication behavior remains functional
• Verified the project builds successfully with the changes

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 demonstrate the feature works or the issue is fixed