Move LoadConfig from config/__init__.py to config/load.py (#24566)

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

tests/test_config.py

@@ -6,8 +6,9 @@ from dataclasses import MISSING, Field, asdict, dataclass, field
 import pytest
 
 from vllm.compilation.backends import VllmBackend
-from vllm.config import (LoadConfig, ModelConfig, PoolerConfig, VllmConfig,
-                         get_field, update_config)
+from vllm.config import (ModelConfig, PoolerConfig, VllmConfig, get_field,
+                         update_config)
+from vllm.config.load import LoadConfig
 from vllm.model_executor.layers.pooler import PoolingType
 from vllm.platforms import current_platform