Should warn about Python 3.12 and Celery

[JohnRDOrazio]

Seeing that Weblate 5 requires at least Python 3.9 which isn't available on Ubuntu 20.04, I went ahead and added the deadsnakes repository. I was then able to install a more recent version of Python, so I figured what the heck and I went and installed Python 3.12. I then updated my virtual environment against Python 3.12, fixed the symlink to point to Python 3.12, and then continued with the Weblate update. I passed first to Weblate 5.0.2 and then to Weblate 5.1.1. I had to force reinstall ffi libraries (only thing that worked was pip install --force-reinstall --no-binary :all: cffi). Migrations went well in both cases.

However, I am having a problem with celery. weblate check --deploy is giving me an error about celery not beating. When I check the celery logs, I see a number of warnings, in particular:
WARNING/Beat] AttributeError: 'cached_property' object has no attribute 'lock'

When doing a search for this error, I found this stackoverflow issue which led to this github celery issue:
Assigning to cached_property is broken on Python 3.12

Basically, celery is currently incompatible with Python 3.12. Perhaps there should be a warning about this under the software requirements section: Python 3.9 or later but not Python 3.12! Until this issue is fixed.

[JohnRDOrazio]

I downgraded my virtual environment to Python 3.11, fixed the symlink for python, re-updated weblate, reinstalled uwsgi, force reinstalled ffi libraries. No migrations were needed this time, and after restarting the celery service and the uwsgi service I no longer get any warnings or errors from weblate check --deploy. My instance is back up and running with Python 3.11 and Weblate 5.1.1.

[nijel]

Documented in #10303, thanks for pointing this out.

[nijel]

Created #10361 to track this.