LabCleaningBot: add unfulfillable_tasks to sync_members_and_tasks()

main.py

@@ -231,6 +231,8 @@ class LabCleaningBot:
                 print("Websockets connection closed. Reestablishing connection.")
 
     async def sync_members_and_tasks(self, session: Session):
+        unfulfillable_tasks = []
+
         while True:
             sync_result = self.sync_members_as_active_users(session)
 
@@ -243,8 +245,11 @@ class LabCleaningBot:
                 reqs = task.create_additional_requests(utc_now(), session)
 
                 if is_err(reqs):
+                    if task not in unfulfillable_tasks:
                         res = self.send_to_base_group("Could not fulfill task: " + task.name)
 
+                        unfulfillable_tasks.append(task)
+
                         if is_err(res):
                             print(res.unwrap_err())
                         else: