BUG: Milestone action errors out

[bsipocz]

It's going on for about a month now, I first noticed it in yaml2ics, but double checking it in other repos, I see the same access issue elsewhere (e.g. lazyloader, spin, networkx, devstats) , thus it's more likely a problem with the action than with the individual repos.

Here is an example run: https://github.com/scientific-python/yaml2ics/actions/runs/10198419456/job/28213280908#step:2:40

Run python -m pip install requests packaging ; echo "MILESTONE=$(
  python -m pip install requests packaging ; echo "MILESTONE=$(
    python /home/runner/work/_actions/scientific-python/attach-next-milestone-action/bc07be829f693829263e57d5e8489f4e57d3d420/next-milestone.py $GITHUB_REPOSITORY
  )" >> $GITHUB_ENV
  shell: /usr/bin/bash --noprofile --norc -e -o pipefail {0}
  env:
    PR: 102
Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: requests in /usr/lib/python3/dist-packages (2.25.1)
Requirement already satisfied: packaging in /usr/local/lib/python3.10/dist-packages (24.1)
Run if [[ $FORCE == true ]]; then
Traceback (most recent call last):
  File "/home/runner/work/_actions/scientific-python/attach-next-milestone-action/bc07be829f693829263e57d5e8489f4e57d3d420/set-pr-milestone.py", line 44, in <module>
    response.raise_for_status()
  File "/usr/lib/python3/dist-packages/requests/models.py", line 943, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: https://api.github.com/repos/scientific-python/yaml2ics/issues/102