Prevent the github action to take forever.

Author: meisterT

.github/workflows/integration.yml

@@ -9,6 +9,7 @@ on:
 jobs:
   integration:
     runs-on: ubuntu-24.04
+    timeout-minutes: 2
     container:
       image: domjudge/gitlabci:24.04
       options: --privileged --cgroupns=host --init