ci: Increase prune time (NVIDIA-NeMo#12860)

Signed-off-by: oliver könig <[email protected]>

Author: ko3n1g

.github/workflows/_test_template.yml

@@ -56,7 +56,7 @@ jobs:
     steps:
       - name: Docker system cleanup
         run: |
-          docker system prune -af --filter "until=8h" --force || true
+          docker system prune -af --filter "until=24h" --force || true
 
       - name: Docker pull image
         run: |