NOTE: Racket CI(GitHub Action) cache

Add the following code helps GitHub Action caches installed packages.

- name: Cache
  uses: actions/[email protected]
  with:
    path: |
      ~/.racket
    key: ${{ runner.os }}-primes

If you install packages via command like:

raco pkg install --auto abc

Then add --skip-installed:

raco pkg install --auto --skip-installed abc