CodeQL scan merge commit instead of PR head

Removes runtime warning

.github/workflows/codeql-analysis.yml

@@ -38,8 +38,9 @@ jobs:
 
     # 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' }}
+     # CodeQL apparently deprecated this feature and now warns on running this command
+    # - run: git checkout HEAD^2
+    #   if: ${{ github.event_name == 'pull_request' }}
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL