Update Optional[x] -> x | None and Union[x, y] to x | y (#26633)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

tests/tool_use/test_jamba_tool_parser.py

@@ -3,7 +3,6 @@
 
 import json
 from collections.abc import Generator
-from typing import Optional
 
 import partial_json_parser
 import pytest
@@ -248,7 +247,7 @@ def test_extract_tool_calls_streaming(
     function_names: list[str] = []
     function_args_strs: list[str] = []
     tool_call_idx: int = -1
-    tool_call_ids: list[Optional[str]] = []
+    tool_call_ids: list[str | None] = []
 
     for delta_message in stream_delta_message_generator(
         jamba_tool_parser, jamba_tokenizer, model_output