v0.44.0

issue-pull.yml now keeps confidential GitLab issues confidential when it
relays them to public GitHub repositories.

- A confidential source issue becomes a generic GitHub issue that links back
  to GitLab. It omits the source title, author, body, attachments, and reply
  contents. Source replies become generic bot comments with the same boundary.
- If an already-relayed public source issue becomes confidential, the next run
  replaces its copied title/body and removes only this workflow's old bot
  replies. Human GitHub comments remain untouched.