Remove contents of /schemas

[dogversioning]

The remaining artifacts in the schema directory have been unused for awhile now, and may be confusing to new users. This removes them - if we need them for reference, we can always go back to any 2.x tag.

Resolves #283

Checklist

• Consider if documentation (like in docs/, or if you've changed the structure of a table) needs to be updated
• Consider if tests should be added
• Update template repo if there are changes to study configuration

[github-actions]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
1996	1981	99%	90%	🟢

New Files

No new covered files...

Modified Files

No covered modified files...

updated for commit: 9c00970 by action🐍

[mikix]

While you're deleting old files, you can probably also delete .pylintrc - but obviously, no rush on that.

[mikix]

Oh also, there is this section of pyproject.toml that can be removed:

# ./cumulus_library/schema needs general revisiting, deferring on style maintenance
# until that occurs
"cumulus_library/schema/valueset.py" = ["E501"]