Fix package detection and installation

[ianmkenney]

basicrta was not being installed correctly, leading to import errors. Specify tool.setuptools.packages.find to automatically find the package and install correctly.

I tested the behavior with code similar to the below code block. Prior to these changes, the import basicrta failed.

micromamba create -p ./env/ python=3.12 -y
micromamba -p ./env/ run pip install ".[test]"

mkdir tmp/ # make sure we can import basicrta outside of the current directory
cd tmp/ && micromamba -p ../env/ run python -c "import basicrta; print(basicrta)"
cd ..
micromamba -p env/ run pytest -v basicrta/tests/ # confirm tests still pass

[rsexton2]

Thank you @ianmkenney, looks good.