Update Cookiecutter

[Zeitsperre]

Changes

• The cookiecutter template has been updated to the latest commit
• RavenPy now uses a src layout
• Documentation has been updated
• HISTORY.rst is now CHANGELOG.rst
• .pre-commit-config.yaml is updated
• ruff checks have replaced the majority of flake8-based checks.
• We now have a CODE_OF_CONDUCT.md
• Dependencies have been synchronized
• Several new workflows have been added
• Many numpy docstrings have been adjusted (WIP)

What's missing?

• The repository requires some secret keys to allow some workflows to succeed.
  • Requests have been made for token generation
    • These have been approved!

[coveralls]

coverage: 81.238% (-0.5%) from 81.752% when pulling 16da9772b8ab2c8ae71671c3f965b7a8819419b9 on cruft-update into cc947f37b8f18b2bf18fb15d5d7b002099b95f23 on master.

[Zeitsperre]

This is just waiting on the tokens to be access token requests to be approved!