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:
@@ -15,40 +15,35 @@ jobs:
     runs-on: ubuntu-latest
 
     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
+      - 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
+        # Override language selection by uncommenting this and choosing your languages
+        # with:
+        #   languages: go, javascript, csharp, python, cpp, java
 
-    # 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
 
-    # 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
 
-    # 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
 
-    # ✏️ 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
 
-    #- run: |
-    #   make bootstrap
-    #   make release
-
-    - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v1
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v1