Close all PRs and issues on GitHub and add commen

comment.py

from github import Github, PullRequest

g = Github("[Personal Access Token]")

r = g.get_repo('ufz/ogs')

for issue in r.get_issues(state='all', direction='asc'):
    comment_str = "OpenGeoSys development has been moved to [GitLab](https://gitlab.opengeosys.org/ogs/ogs).\n\n"
    try:
      pr = issue.as_pull_request()
    except:
      print(f"IS ISSUE: {issue.number}")
      comment_str += f"[See this issue on GitLab](https://gitlab.opengeosys.org/ogs/ogs/-/issues/{issue.number})."
    else:
      print(f"IS PR: {pr.number}")
      comment_str += f"[See this pull request on GitLab](https://gitlab.opengeosys.org/ogs/ogs/-/merge_requests/{pr.number})."

    if issue.state != 'closed':
        issue.edit(state='closed')
        comment_str += f"\n\nThis issue / pull request was **open** before the GitLab migration."

    issue.create_comment(comment_str)
    print(comment_str)