Upgraded packaging infrastructure

[IanLee1521]

Ref:

• https://build.pypa.io/en/stable/installation.html
• https://packaging.python.org/en/latest/guides/writing-pyproject-toml/
• https://packaging.python.org/en/latest/guides/modernize-setup-py-project/

[IanLee1521]

fyi to @LRWeber about this change.

[LRWeber]

We may also want to delete requirements.txt since it references the other deleted file.

[LRWeber]

Our automated testing action currently has the dev dependencies hardcoded.
https://github.com/LLNL/scraper/blob/9593f4a843fde58063e6ff2b008471ef79e340ce/.github/workflows/main.yml#L34-L37
Should it be using a different command to leverage the dependency list(s) in the .toml file (e.g. pip install .[dev])? Or is it specifically using a minimal list? (And if that's the case, should that be another list defined in the .toml file?)

[IanLee1521]

@LRWeber - good catches! I just updated the actions file to convert over to using the definition out of the pyproject.toml file instead. Good catch!

[jsf9k]

I came to check if there was a PR to do this very thing!

[mcdonnnj]

@LRWeber Any chance this can be merged?