ci: codeql fix deprecated checkout HEAD^2

Author: markus-wa

.github/workflows/codeql-analysis.yml

@@ -2,10 +2,10 @@ name: "CodeQL"
 
 on:
   push:
-    branches: [master, v0.5, v1]
+    branches: [master, v3]
   pull_request:
     # The branches below must be a subset of the branches above
-    branches: [master]
+    branches: [master, v3]
   schedule:
     - cron: '0 1 * * 4'
 
@@ -22,33 +22,11 @@ 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
-      # Override language selection by uncommenting this and choosing your languages
-      # with:
-      #   languages: go, javascript, csharp, python, cpp, java
 
-    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
-    # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
       uses: github/codeql-action/autobuild@v1
 
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 https://git.io/JvXDl
-
-    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
-    #    and modify them (or add more) to build your code if your project
-    #    uses a compiled language
-
-    #- run: |
-    #   make bootstrap
-    #   make release
-
     - name: Perform CodeQL Analysis
       uses: github/codeql-action/analyze@v1