message: Add merging the v1 release PR to the checklist
diff: @@ -30,7 +30,7 @@ def branch_exists_on_remote(branch_name):
  return run_git('ls-remote', '--heads', ORIGIN, branch_name).strip() != ''
  # Opens a PR from the given branch to the release branch
  -def open_pr(repo, all_commits, short_main_sha, new_branch_name, source_branch, target_branch, conductor, include_mergeback_in_changelog):
  +def open_pr(repo, all_commits, short_main_sha, new_branch_name, source_branch, target_branch, conductor, is_v2_to_v1_backport):
  # Sort the commits into the pull requests that introduced them,
  # and any commits that don't have a pull request
  pull_requests = []
  @@ -79,8 +79,9 @@ def open_pr(repo, all_commits, short_main_sha, new_branch_name, source_branch, t
  body.append(' - [ ] The CHANGELOG includes all relevant, user-facing changes since the last release.')
  body.append(' - [ ] There are no unexpected commits being merged into the ' + target_branch + ' branch.')
  body.append(' - [ ] The docs team is aware of any documentation changes that need to be released.')
  - if include_mergeback_in_changelog:
  + if not is_v2_to_v1_backport:
  body.append(' - [ ] The mergeback PR is merged back into ' + source_branch + ' after this PR is merged.')
  + body.append(' - [ ] The v1 release PR is merged after this PR is merged.')
  title = 'Merge ' + source_branch + ' into ' + target_branch
  @@ -273,7 +274,7 @@ def main():
  source_branch=args.source_branch,
  target_branch=args.target_branch,
  conductor=args.conductor,
  - include_mergeback_in_changelog=not args.perform_v2_to_v1_backport
  + is_v2_to_v1_backport=args.perform_v2_to_v1_backport
  )
  if __name__ == '__main__':
  