test: only run new test on pydantic v2

Author: ryangalamb

tests/test_pydantic/test_generic.py

@@ -74,6 +74,7 @@ def test_invalid_generics(data_type, data_value, error_loc, error_type):
     assert error_dict["type"] == error_type
 
 
+@needs_pydanticv2
 def test_generic_json_schema():
     schema = Response[DataModel].model_json_schema()
     # Should have referenced the schema in $defs