### NOTE
* We shouldn't merge this PR until GCP cloud functions drops support for Python 3.7 ([Currently scheduled for GCF](https://cloud.google.com/functions/docs/runtime-support#python))
As part of supporting Python 3.12, we're now officially drop support for Python 3.7.
This PR:
* Changed supported Python version from 3.7 to 3.8 in README.
* Replaced distribution test image from `debian:buster` to `debian:bullseye` since the default Python version in buster is 3.7.
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Closes#34450
PiperOrigin-RevId: 622899511
* Add Python 3.10.0rc1 binary wheels
* Drop Python 3.5 artifacts
* Document the drop of 3.5
* Fix the wrong pip pointer
* Update manylinux2014 to a newer version, remove 3.5 distribtest
* Update manylinux aarch64 to see if the absl error go away
* Use the preferred alias
* Allow different wheel library to produce different tag order
* Remove unused shell var and log produced wheels
* Use copy instead of move
* Make bash happy about the wildcard
* Upgrade the debian image to use 3.5+ Python
* Polish the comments for the Dockerfiles
* Remove Python 2.7 binary wheels
* Make sure pip won't pick-up newer versions
* Attempt to fix the distribtest
* Fallback to virtualenv==16.7.9 for 34 and 35
* Remove 34 from binary wheel distribtests
- add rubocop as a dev dependency
- fixed many style violations it reported, often using --auto-correct
- add a rubocop config
- .rubocop.yml shows the exceptions
- .rubocopy_todo.yml tracks outstanding style issues
- adds a rake task to allow rubocop styling checks to be automated