[chore] Add Linters to PR Workflows

.github/workflows/lint.yml

@@ -0,0 +1,21 @@
+name: Run Linters
+
+on: [pull_request]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Set up Ruby
+      run: ruby/setup-ruby@v1
+
+    - name: Install dependencies
+      run: |
+        gem install bundler -v 2.4.22
+        bundle install --jobs 4 --retry 3
+
+    - name: Run linters
+      run: bundle exec rubocop