Format the provenance test so ruff stops failing on it

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H7LwYgJfpkbLCTeiAf8U4A

backend/tests/flow/test_provenance.py

@@ -74,9 +74,7 @@ def test_a_value_from_a_dashboard_says_so_rather_than_blaming_a_node():
 
     pipeline.publish(
         {"house.temp": 25.0},
-        ValueSource(
-            kind="dashboard", id="panel", label="Setpoint", detail="slider"
-        ),
+        ValueSource(kind="dashboard", id="panel", label="Setpoint", detail="slider"),
     )
 
     published = [e for e in events if e["type"] == "message_value"]