style: black formatting

Author: Nissan Pow

test/ux/core/flows/basic/fail_flow.py

@@ -15,6 +15,9 @@ def start(self):
     @step
     def failing_step(self):
         raise RuntimeError("Deliberate failure for testing scheduler status reporting.")
+        self.next(
+            self.end
+        )  # noqa: unreachable — required for Metaflow's graph validator
 
     @step
     def end(self):