fix(common_utils.py): add unit test to ensure custom_endpoint=False is handled correctly

Fixes https://github.com/BerriAI/litellm/issues/9915

tests/litellm/llms/databricks/test_databricks_common_utils.py

@@ -0,0 +1,32 @@
+import json
+import os
+import sys
+
+import pytest
+from fastapi.testclient import TestClient
+
+sys.path.insert(
+    0, os.path.abspath("../../../..")
+)  # Adds the parent directory to the system path
+from unittest.mock import MagicMock, patch
+
+from litellm.llms.databricks.common_utils import DatabricksBase
+
+
+def test_databricks_validate_environment():
+    databricks_base = DatabricksBase()
+
+    with patch.object(
+        databricks_base, "_get_databricks_credentials"
+    ) as mock_get_credentials:
+        try:
+            databricks_base.databricks_validate_environment(
+                api_key=None,
+                api_base="my_api_base",
+                endpoint_type="chat_completions",
+                custom_endpoint=False,
+                headers=None,
+            )
+        except Exception:
+            pass
+        mock_get_credentials.assert_called_once()