fix(types): Add cast for HybridCloudForeignKey in test fixture

Add isinstance check and cast to narrow the generic type parameters for
HybridCloudForeignKey fixture return type.

Author: JoshFerge

tests/sentry/deletions/tasks/test_hybrid_cloud.py

@@ -92,7 +92,11 @@ def reset_watermarks() -> None:
 
 @pytest.fixture
 def saved_search_owner_id_field() -> HybridCloudForeignKey[int, int]:
-    return SavedSearch._meta.get_field("owner_id")
+    from typing import cast
+
+    field = SavedSearch._meta.get_field("owner_id")
+    assert isinstance(field, HybridCloudForeignKey)
+    return cast(HybridCloudForeignKey[int, int], field)
 
 
 @django_db_all