chore: Add CodeQL Actions Ruby Beta (#931)

Fixes #767

.github/workflows/codeql.yml

@@ -0,0 +1,37 @@
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+  workflow_dispatch:
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+
+    env:
+      CODEQL_ENABLE_EXPERIMENTAL_FEATURES: true
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'ruby' ]
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v2
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v1
+      with:
+        tools: latest
+
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v1
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v1