Fix order of OS CI cleanup (#6714)

scripts/openstack-cleanup/main.py

@@ -34,14 +34,14 @@ def main():
 
     conn = openstack.connect()
 
-    print('Security groups...')
-    map_if_old(conn.network.delete_security_group,
-               conn.network.security_groups())
-
     print('Servers...')
     map_if_old(conn.compute.delete_server,
                conn.compute.servers())
 
+    print('Security groups...')
+    map_if_old(conn.network.delete_security_group,
+               conn.network.security_groups())
+
     print('Subnets...')
     map_if_old(conn.network.delete_subnet,
                conn.network.subnets())