docs: use RST inline code in tool-call release note

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: chuenchen309

releasenotes/notes/fix-openai-toolcall-empty-arguments-53c5621622bc1866.yaml

@@ -1,8 +1,8 @@
 ---
 fixes:
   - |
-    Fixed `ChatMessage.from_openai_dict_format` crashing on zero-argument tool
+    Fixed ``ChatMessage.from_openai_dict_format`` crashing on zero-argument tool
     calls. OpenAI-compatible servers (vLLM, llama.cpp, Ollama, LM Studio, ...) may
-    send an empty string or omit the `arguments` field for a tool call that takes
-    no arguments; this previously raised `json.JSONDecodeError` or `KeyError`.
-    Such tool calls are now parsed into a `ToolCall` with empty `arguments`.
+    send an empty string or omit the ``arguments`` field for a tool call that takes
+    no arguments; this previously raised ``json.JSONDecodeError`` or ``KeyError``.
+    Such tool calls are now parsed into a ``ToolCall`` with empty ``arguments``.