fixup! Update rspec github action ruby matrix

Author: paul

.github/workflows/rspec.yml

@@ -19,6 +19,7 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true # runs 'bundle install' and caches installed gems automatically
       - name: Install dependencies
         run: |
           gem install bundler --no-document