[enhancement] Clean POSYDON repository

[maxbriel]

This pull request:

• Updates the setuptools we use.
• Moves from versioneer.py to setuptools-scm for easier intergration.
• Automatically updates the conda.yaml version.
• Moves project definitions and requirements into pyproject.toml instead of defining them inside setup.py.
• Cleans up test CI by adding project parameters to pyproject.toml.

[astroJeff]

Needs proper testing. @sgossage can you help out with this?

[sgossage]

Should we revert to the old version: "{{ version }}"?

Otherwise I think we can test if this works for us with a release after merging.

[sgossage]

Things seem to be working well. In my local test of publish_conda, the tag v2.2.4 gets picked up, I think because that is the latest tag this branch can grab.

[astro-abhishek]

minor stylistic suggestion: leave the quotes on

version: "{{ GIT_DESCRIBE_TAG }}"

[sgossage]

There have been a few updates to the ubuntu-latest image in March it looks like and now the Github actions involving that image are failing. These could be related. To restore things, it looks like we need to update the test coverage.