Fixes #1913 - Adds setting to change the PR associated to a given commit

[aaron-skydio]

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Description

Currently, the pull request selected for a commit is the most recently updated one. As mentioned in #1913, this is not always desired, for example when a feature merges to one branch, and then that branch is merged into additional branches.

This adds a setting to order by updated or created time, ascending or descending. It preserves the other behavior, of preference based on owner and merged status.

Checklist

• I have followed the guidelines in the Contributing document
• My changes follow the coding style of this project
• My changes build without any errors or warnings
• My changes have been formatted and linted
• My changes include any required corresponding changes to the documentation (including CHANGELOG.md and README.md)
• My changes have been rebased and squashed to the minimal number (typically 1) of relevant commits
• My changes have a descriptive commit message with a short title, including a Fixes $XXX - or Closes #XXX - prefix to auto-close the issue that your PR addresses

[nocnokneo]

This would solve our GitOps workflow where we first merge changes to main then later use a PR approval process to merge main -> deploy/prod. Those PRs targetting deploy/prod, deploy/test, etc are not interesting.