Unit Tests for PPE calcs

Incorporate tests in git actions to ensure that PPE estimates are in the right neighborhood

This is something Penn is still working through - mostly uses the [excel](https://drive.google.com/file/d/1zoiy7hJJJPgXrljN6-PIYh_0leRNl1Ec/view?usp=sharing) file to check against.

Use the linked Excel workbook as the current reference for PPE estimates, then locate the Python PPE calculation entry points and the repository's GitHub Actions configuration. Determine which expected values define the acceptable neighborhood and add automated checks that run in GitHub Actions. Done means the PPE estimates are covered by tests and the checks pass.

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