[Archery][Release] Archery fails adding comments to PRs #50336

Pushed job identifier is: `release-25.0.0-rc0-1`
Traceback (most recent call last):
  File "/home/raulcd/code/archery/bin/archery", line 7, in <module>
    sys.exit(archery())
             ~~~~~~~^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 1462, in __call__
    return self.main(*args, **kwargs)
           ~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 1383, in main
    rv = self.invoke(ctx)
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 1850, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 1850, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 1246, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/core.py", line 814, in invoke
    return callback(*args, **kwargs)
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/click/decorators.py", line 46, in new_func
    return f(get_current_context().obj, *args, **kwargs)
  File "/home/raulcd/code/arrow/dev/archery/archery/crossbow/cli.py", line 325, in report_pr
    pull_request = target_arrow.github_pr(title=pr_title,
                                          github_token=queue.github_token,
                                          create=False)
  File "/home/raulcd/code/arrow/dev/archery/archery/crossbow/core.py", line 571, in github_pr
    for pull in repo.get_pulls(state="open", head=head, base=base):
                ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/raulcd/code/archery/lib/python3.13/site-packages/github/Repository.py", line 3438, in get_pulls
    assert is_optional(base, str), base
           ~~~~~~~~~~~^^^^^^^^^^^
AssertionError: None