Increase polling time to 3 hours

Author: RealCLanger

.github/workflows/sync-fork-checks.yml

@@ -108,7 +108,7 @@ jobs:
           # job name → fork job HTML URL
           declare -A JOB_URLS
 
-          MAX_POLL=90
+          MAX_POLL=180
           POLL=0
           OVERALL_CONCLUSION=""