lint: fix line length violation (#3017)

Signed-off-by: Milas Bowman <[email protected]>

Author: milas

docker/types/services.py

@@ -436,7 +436,8 @@ def __init__(self, parallelism=0, delay=None, failure_action='continue',
 
 class RollbackConfig(UpdateConfig):
     """
-    Used to specify the way container rollbacks should be performed by a service
+    Used to specify the way container rollbacks should be performed by a
+    service
 
     Args:
         parallelism (int): Maximum number of tasks to be rolled back in one