Small docstring clarification in _find_zombies (apache#24930)

Author: dstandish

airflow/jobs/scheduler_job.py

@@ -1358,8 +1358,8 @@ def check_trigger_timeouts(self, session: Session = None):
     def _find_zombies(self, session):
         """
         Find zombie task instances, which are tasks haven't heartbeated for too long
-        or have a no-longer-running LocalTaskJob, and send them off to the DAG processor
-        to be handled.
+        or have a no-longer-running LocalTaskJob, and create a TaskCallbackRequest
+        to be handled by the DAG processor.
         """
         self.log.debug("Finding 'running' jobs without a recent heartbeat")
         limit_dttm = timezone.utcnow() - timedelta(seconds=self._zombie_threshold_secs)