Workaround an unrelated typing problem

Author: johnslavik

scripts/gen_credits.py

@@ -55,7 +55,11 @@ def _extra_marker(req: Requirement) -> str | None:
     if not req.marker:
         return None
     try:
-        return next(marker[2].value for marker in req.marker._markers if getattr(marker[0], "value", None) == "extra")
+        return next(
+            marker[2].value  # type: ignore[union-attr]
+            for marker in req.marker._markers
+            if getattr(marker[0], "value", None) == "extra"
+        )
     except StopIteration:
         return None