glab mr merge

Merge GitLab merge requests. More information: https://glab.readthedocs.io/en/latest/mr/merge.html.

• Merge the merge request associated with the current branch interactively:
  glab mr merge
• Merge the specified merge request, interactively:
  glab mr merge {{mr_number}}
• Merge the merge request, removing the branch on both the local and the remote:
  glab mr merge --remove-source-branch
• Squash the current merge request into one commit with the message body and merge:
  glab mr merge --squash --message="{{commit_message_body}}"
• Display help:
  glab mr merge --help