fix(test): remove redundant @flow decorator breaking collection on prefect 2.20/py3.13

Author: simontaurus

tests/utils/workflow_test.py

@@ -34,7 +34,6 @@
     ],
     log_prints=True,
 )
-@flow
 def osw_python_teams_notify_test_flow():
     """Notify Microsoft Teams channel using a webhook"""
     return 42