Fix typing for StepReport args

Author: youtux

src/pytest_bdd/reporting.py

@@ -28,8 +28,8 @@
 class StepReport:
     """Step execution report."""
 
-    failed = False
-    stopped = None
+    failed: bool = False
+    stopped: float | None = None
 
     def __init__(self, step: Step) -> None:
         """Step report constructor.