Use `is_read_only` to allow/forbid to update Worker Activity

Closes #229 (closed)

arkindex_worker/worker/__init__.py

@@ -278,10 +278,6 @@ class ElementsWorker(
         ), "element_id shouldn't be null and should be an UUID or str"
         assert isinstance(state, ActivityState), "state should be an ActivityState"
 
-        if self.is_read_only:
-            logger.warning("Cannot update activity as this worker is in read-only mode")
-            return True
-
         try:
             self.request(
                 "UpdateWorkerActivity",