Introduce Python 3.12 image generation
- [x] Introduce with `gcc` and `libffi-dev` installed in the meantime
- [x] Use `rc` tag, unstable Python version
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- [x] Move `pre-commit` and `git` installation from `3.11` to `3.12` image.
- [x] Remove `gcc` and `libffi-dev` once no longer necessary: Until `dulwich, msgpack, rapidfuzz, cffi` wheels for Py3.12 are provided to install `poetry`
- [x] Remove `rc` tag once Python 3.12 is released as stable
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- [x] Create follow-up ticket for Py 3.13: #10+
issue