try to ensure all required log file exist before submission

• message cleanup for external workflows

shared/workspaces/workspaces/workflow/services/workflow_service.py

@@ -804,6 +804,8 @@ class WorkflowService(WorkflowServiceIF):
             return True
         else:
             logger.warning(f"Failed to create {logfile}. Trying again")
+            # sleep slightly, but not too long, and try again
+            sleep(0.5)
             iteration += 1
             self._create_base_logfile(logfile, iteration)