Cache ruby deps

Author: sverhoeven

.github/workflows/ci.yml

@@ -6,14 +6,23 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-16.04
+    runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v2
     - name: Setup Ruby
       uses: ruby/[email protected]
       with:
-        ruby-version: 2.5
-        bundler-cache: true
+        ruby-version: 2.7
+    - name: Bundle path
+      run: |
+        bundle config path .vendor/bundle
+    - name: Cache Ruby deps
+      uses: actions/cache@v2
+      with:
+        path: .vendor/bundle
+        key: ruby-${{ matrix.os }}-${{ matrix.ruby }}-${{ hashFiles('**/Gemfile.lock') }}
+        restore-keys: |
+          ruby-${{ matrix.os }}-${{ matrix.ruby }}-
     - name: Ruby deps
       run: gem install json kramdown jekyll bundler
     - name: Setup Python