Switch CI to use ruby/setup-ruby action (#2659)

.github/workflows/main.yml

@@ -36,22 +36,12 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
 
-      - name: Install Ruby ${{ env.RUBY_VERSION }}
-        uses: actions/setup-ruby@v1
+      - name: Ruby Setup + Bundle Install
+        uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ env.RUBY_VERSION }}
+          bundler-cache: true 
 
-      - name: Bundle cache
-        uses: actions/cache@v2
-        with:
-          path: vendor/bundle
-          key: ${{ runner.os }}-gems-${{ hashFiles('**/Gemfile.lock') }}
-          restore-keys: |
-            ${{ runner.os }}-gems-
-      - name: Bundle install
-        run: |
-          bundle config path vendor/bundle
-          bundle install --jobs 4 --retry 3
       - name: Setup database
         run:  |
           bundler exec rails db:create RAILS_ENV=test