Prevent bundle run when cache hit

.github/workflows/build.yaml

@@ -12,12 +12,14 @@ jobs:
     steps:
       - uses: actions/checkout@v1
       - uses: actions/cache@v1
+        id: bundler-cache
         with:
           path: vendor/bundle
           key: ${{ runner.os }}-gems-${{ hashFiles('**/Gemfile.lock') }}
           restore-keys: |
             ${{ runner.os }}-gems-
       - name: Bundle install
+        if: steps.bundler-cache.outputs.cache-hit != 'true'
         run: |
           bundle config path vendor/bundle
           bundle install --jobs 4 --retry 3