cleanup: Remove unused imports from speculators_eagle.py

- Remove unused Any, Dict, Optional imports
- Remove unused AutoConfig import
- Keep only Union which is actually used in type annotations

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: rahul-tuli

vllm/transformers_utils/configs/speculators_eagle.py

@@ -4,7 +4,7 @@
 import json
 import os
 from pathlib import Path
-from typing import Optional, Union
+from typing import Union
 
 from transformers import PretrainedConfig