Add pyproject.toml for certbot (#10402)

This sets up a `pyproject.toml` file for certbot, initially generated
[using](https://hatch.pypa.io/latest/intro/#existing-project) `hatch new
--init` and modifying from there. Since we dynamically require acme of a
matching version, I kept that around in `setup.py` to do the simplest
thing in this PR.

Other possible (future) implementations:
- setuptools has a beta implementation to read from a
`requirements.txt`. we could generate one of those.
- we could just hardcode it and update at release time. I like not
having to keep the version up to date in various places but maybe it's
actually fine
- something something integration with poetry pinning?

I think the syntax for setting version dynamically in `pyproject.toml`
is much nicer than what we do in `setup.py`. It's a little silly to do
it there after we've bothered to calculate it, but I put it there in the
hopes of being able to remove it from `setup.py` someday/somehow.

It would be nice to access the version dynamically set in
`pyproject.toml` in `setup.py`, but I do not think it is likely to be
possible.

Here are some useful links regarding this migrations:
- [How to modernize a `setup.py` based
project?](https://packaging.python.org/en/latest/guides/modernize-setup-py-project/)
- [Writing your
`pyproject.toml`](https://packaging.python.org/en/latest/guides/writing-pyproject-toml/)
- [Configuring setuptools using `pyproject.toml` files](
https://setuptools.pypa.io/en/latest/userguide/pyproject_config.html)
- [`pyproject.toml`
specification](https://packaging.python.org/en/latest/specifications/pyproject-toml/)
- [Platform compatibility
tags](https://packaging.python.org/en/latest/specifications/platform-compatibility-tags/)

newsfragments/10402.changed

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+Migrated most functionality from `certbot/setup.py` to `certbot/pyproject.toml`