Setup GitHub Actions Continuous Integration tests

[weiji14]

What I am changing

• Add Continuous Integration tests for every Pull Request and push to the main branch

How I did it

• Added an integration test under src/tests/test_datapipe.py to ensure LightningCLI from Setup LightningCLI trainer script #24 works
• Add GitHub Actions workflow in .github/workflows/test.yml which runs on Ubuntu-22.04 and Python 3.11
  • Uses https://github.com/mamba-org/setup-micromamba to install dependencies
  • Note that the conda-lock.yml lockfile is used, since micromamba support it! However, we're installing pytest separately instead of adding it to the environment.yml file.
• Also added a .gitignore file

How you can test it

• Install pytest and run python -m pytest --verbose src/tests/ locally

Related Issues

Based on developmentseed/chabud2023#5

[weiji14]

Merging directly since unit tests pass, and we're trying to move fast. Will follow up with other CI stuff like linters which are less critical and can go through a more proper review cycle.