Merge pull request #5086 from github/update-codeql-workflow

Update CodeQL workflow

Author: tibbes

.github/workflows/codeql-analysis.yml

@@ -2,7 +2,13 @@ name: "Code scanning - action"
 
 on:
   push:
+    branches:
+      - main
+      - 'rc/*'
   pull_request:
+    branches:
+      - main
+      - 'rc/*'
   schedule:
     - cron: '0 9 * * 1'
 
@@ -14,16 +20,7 @@ jobs:
     steps:
     - name: Checkout repository
       uses: actions/checkout@v2
-      with:
-        # We must fetch at least the immediate parents so that if this is
-        # a pull request then we can checkout the head.
-        fetch-depth: 2
-
-    # If this run was triggered by a pull request event, then checkout
-    # the head of the pull request instead of the merge commit.
-    - run: git checkout HEAD^2
-      if: ${{ github.event_name == 'pull_request' }}
-      
+
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v1