Cache webpacker and assets precombile

cache_assets_precompilation.yml

# Source: https://github.community/t/cache-rails-assets-generated-by-webpacker/189057/4
- name: Get Webpacker cache key
  id: get-webpacker-cache-key
  run: |
    echo "::set-output name=key::$(bin/rails r 'print Webpacker::Instance.new.compiler.send(:watched_files_digest)')"
  shell: bash

  - name: Cache precompiled assets
  uses: actions/cache@v3
  with:
    path: |
      public/packs-test
      tmp/cache/webpacker
    key: ${{ runner.os }}-assets-${{ steps.get-webpacker-cache-key.outputs.key }}
    restore-keys: |
      ${{ runner.os }}-assets-