Simplify codeql github action (microsoft#44124)

sandersn · web-flow · commit 82cb50fa4543 · 2021-05-17T11:13:30.000-07:00
The current action is failing with an error that recommends removing the
`git checkout HEAD^2` step.
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
@@ -20,11 +20,6 @@ jobs:
         # 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
