build.yml bugfix

Author: CodeMeister

.github/workflows/build.yml

@@ -28,7 +28,7 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: ${{ matrix.ruby }
+        ruby-version: ${{ matrix.ruby }}
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically
 
     - name: Run Tests