Updating CI workflow

[mattkwiecien]

This PR aims to expand our test coverage and unify the CI workflow with the regular development workflow. This is useful because we want the build action to reflect the development workflow that a user who is contributing to the codebase would experience. Currently the two are pretty disjointed (different installs etc).

• Combined lint and test into one single ci.yaml file
• Expanded our CI to test on both macOS and Ubuntu, and testing both 3.8 and 3.11. We can test in between versions, but I think that may be overkill

The new workflow is lint > tests > publish

• Lint
  • Replaced manual install of flake8, black, and coveralls with their associated published github action
• Tests
  • Using mamba for speed and installing from our new environment.yml file
  • Updated environment.yml to include all development dependencies, and instructing a user to pip install with --no-deps to prevent dependency clashes. Removing defaults from channels to prevent similar issues
  • Added cache that resets daily for each mamba environment.
  • NOTE: writing to .coverage isn't thread safe, so changed our testing workflow to run ALL tests, and generate a coverage report. THEN run the mpi tests in parallel, but do not generate a coverage report from them.
  • Lastly, post to coveralls and then wait for the finish webhook to complete the coverage report
• Publish
  • Post to coveralls.io and let them know all tests are finished.

[mattkwiecien]

@carlosggarcia Ready to review, finally!

[mattkwiecien]

Note that the build check will never pass as it's been changed. We will need to update this once the PR is merged.