Bump Python 3 to 3.12 (#18212)

* bump py version to 3.12

* update dbm dev container

* update builders and build deps

* fix python string

* Build lxml dependencies for linux x64 (#18467)

* fix rmq version

* fix gunicorn tests

* Fix lock file generation

* comment out if clause to force dep resolution

* bump python to 3.12.6

* fix python on Windows sha

* remove DD_PYTHON2 unbound variable

* fix hatch errors

* remove setup.py files

* fix CI

* revert datadog_checks_test_helper

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Co-authored-by: Alex Lopez <[email protected]>
Co-authored-by: Ilia Kurenkov <[email protected]>
Co-authored-by: Alex Lopez <[email protected]> 69cffd9