removed git checkout from CodeQL workflow

.github/workflows/codeql-analysis.yml

@@ -2,12 +2,12 @@ name: "CodeQL"
 
 on:
   push:
-    branches: [master, ]
+    branches: [master]
   pull_request:
     # The branches below must be a subset of the branches above
     branches: [master]
   schedule:
-    - cron: '0 4 * * 5'
+    - cron: "0 4 * * 5"
 
 jobs:
   analyse:
@@ -22,11 +22,6 @@ 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