chore: pin GitHub Actions to commit SHA (#729)

Signed-off-by: Quentin Laplanche <quentin.laplanche@docker.com>

.github/workflows/codeql-analysis.yml

@@ -16,15 +16,15 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v2
+      uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
 
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v1
+      uses: github/codeql-action/init@231aa2c8a89117b126725a0e11897209b7118144 # v1
       with:
         languages: ${{ matrix.language }}
 
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v1
+      uses: github/codeql-action/autobuild@231aa2c8a89117b126725a0e11897209b7118144 # v1
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v1
+      uses: github/codeql-action/analyze@231aa2c8a89117b126725a0e11897209b7118144 # v1