[Chore]: Stream tokens vs characters in tool call parser tests (#26513)

Signed-off-by: Ben Browning <bbrownin@redhat.com>

tests/entrypoints/openai/tool_parsers/conftest.py

@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import pytest
+from transformers import AutoTokenizer
+
+from vllm.transformers_utils.tokenizer import AnyTokenizer
+
+
+@pytest.fixture(scope="function")
+def default_tokenizer() -> AnyTokenizer:
+    return AutoTokenizer.from_pretrained("gpt2")