sourceCommit
The full commit ID of the tip of the source branch used to create the pull request. If the pull request branch is updated by a push while the pull request is open, the commit ID changes to reflect the new tip of the branch.
The full commit ID of the tip of the source branch used to create the pull request. If the pull request branch is updated by a push while the pull request is open, the commit ID changes to reflect the new tip of the branch.