chore: update mock server docs

Author: stainless-app[bot]

CONTRIBUTING.md

@@ -88,8 +88,7 @@ $ pip install ./path-to-wheel-file.whl
 Most tests require you to [set up a mock server](https://github.com/stoplightio/prism) against the OpenAPI spec to run the tests.
 
 ```sh
-# you will need npm installed
-$ npx prism mock path/to/your/openapi.yml
+$ ./scripts/mock
 ```
 
 ```sh

tests/api_resources/beta/messages/test_batches.py

@@ -442,7 +442,7 @@ def test_method_results(self, client: Anthropic, respx_mock: MockRouter) -> None
         assert i == 1
         assert results.http_response.is_stream_consumed
 
-    @pytest.mark.skip(reason="Prism doesn't support application/x-jsonl responses")
+    @pytest.mark.skip(reason="Mock server doesn't support application/x-jsonl responses")
     @parametrize
     def test_path_params_results(self, client: Anthropic) -> None:
         with pytest.raises(ValueError, match=r"Expected a non-empty value for `message_batch_id` but received ''"):
@@ -875,7 +875,7 @@ async def test_method_results(self, async_client: AsyncAnthropic, respx_mock: Mo
         assert i == 1
         assert results.http_response.is_stream_consumed
 
-    @pytest.mark.skip(reason="Prism doesn't support application/x-jsonl responses")
+    @pytest.mark.skip(reason="Mock server doesn't support application/x-jsonl responses")
     @parametrize
     async def test_path_params_results(self, async_client: AsyncAnthropic) -> None:
         with pytest.raises(ValueError, match=r"Expected a non-empty value for `message_batch_id` but received ''"):