Add proper type annotation to the workflow request

services/workflow/workflow/server.py

@@ -511,7 +511,7 @@ class WorkflowRequestRestService:
             body=f"SUCCESS for identifier '{identifier}': Sent '{msg_type}' to AAT for this workflow's SDM",
         )
 
-    def get_contacts(self, requested_workflow) -> str:
+    def get_contacts(self, requested_workflow: WorkflowRequest) -> str:
         """
         Method that retrieves the PI/CoI email information for a given workflow
         request