Switch packaging from setup.py to pyproject.toml

[harshil21]

What kind of feature are you missing? Where do you notice a shortcoming of PTB?

PTB currently builds the wheels for uploading to PyPI by running the command python setup.py sdist bdist_wheel (from the wiki). However, the use of that command is deprecated.

The reason we are still using setup.py is because we wanted to dynamically build the wheels for both PTB and PTB-raw, and not have two separate repositories or files for that purpose. However, upon some observation, PTB has now made all its dependencies except httpx optional. This negates the need for having PTB-raw in the first place.

Additionally, the number of downloads for PTB-raw is tiny (12k/mo vs 1M/mo).

Describe the solution you'd like

Follow the packaging guide to migrate, and make sure that our build system follows the recommended guidelines. And then remove the PTB-raw package.

Describe alternatives you've considered

We could still keep setup.py, but we have to stop using that setup.py command to build wheels.

Additional context

No response