Merge pull request #11520 from jbradberry/fix-register-peers

In register_peers, only check non-empty flags for the 1-cycle check

awx/main/management/commands/register_peers.py

@@ -37,7 +37,7 @@ class Command(BaseCommand):
 
         # No 1-cycles
         for collection in ('peers', 'disconnect', 'exact'):
-            if options['source'] in options[collection]:
+            if options[collection] and options['source'] in options[collection]:
                 raise CommandError(f"Source node {options['source']} may not also be in --{collection}.")
 
         # No 2-cycles