Refa: Test configs (#8220)

### What problem does this PR solve?

- Move common constants (HOST_ADDRESS, INVALID_API_TOKEN, etc.) to
configs.py
- Update test imports to use centralized configs
- Clean up duplicate constant definitions across test files

This improves maintainability by centralizing configuration.

### Type of change

- [x] Refactoring test case

test/testcases/test_http_api/test_dataset_mangement/test_delete_datasets.py

@@ -18,11 +18,11 @@ from concurrent.futures import ThreadPoolExecutor, as_completed
 
 import pytest
 from common import (
-    INVALID_API_TOKEN,
     batch_create_datasets,
     delete_datasets,
     list_datasets,
 )
+from configs import INVALID_API_TOKEN
 from libs.auth import RAGFlowHttpApiAuth
 
 

test/testcases/test_http_api/test_dataset_mangement/test_list_datasets.py

@@ -17,7 +17,8 @@ import uuid
 from concurrent.futures import ThreadPoolExecutor, as_completed
 
 import pytest
-from common import INVALID_API_TOKEN, list_datasets
+from common import list_datasets
+from configs import INVALID_API_TOKEN
 from libs.auth import RAGFlowHttpApiAuth
 from utils import is_sorted