Assume we're in prod unless we know we aren't

Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>

playbooks/roles/flag_build_commits/files/flag_commit_build.py

@@ -43,7 +43,7 @@ def _koji_link(msg):
         raise NotImplementedError("Unhandled instance")
 
     # One last little switch-a-roo for stg
-    if '.stg.' in msg['request'][0]:
+    if msg['request'] and '.stg.' in msg['request'][0]:
         base = "https://koji.stg.fedoraproject.org/koji"
 
     return base + "/taskinfo?taskID=%i" \