comment for sleep in test

Author: d-w-moore

irods/test/data_obj_test.py

@@ -3002,6 +3002,8 @@ def test_modified_sorting_of_replicas__issue_746(self):
                 # Ensure that one of the replicas is stale, to test proper sorting.
                 with data.open('a', **{kw.RESC_NAME_KW: newResc1}) as f:
                     f.write(b'.')
+
+                # Sleep to ensure different replica modify timestamps.
                 time.sleep(2)
 
                 data.replicate(resource=newResc2)