ci: bump checkout action to 5.0.0 in docker-build action (#289)

Author: sdn4z

.github/actions/docker-build/action.yml

@@ -39,7 +39,7 @@ runs:
   using: "composite"
   steps:
     - name: Checkout repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@e468171a9de216ec08956ac3ada2f0791b6bd435 # v3.11.1