fix: Resolve issue with vector url usage (#1395)

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cognee/infrastructure/databases/vector/config.py

@@ -39,7 +39,7 @@ class VectorConfig(BaseSettings):
             values.vector_db_url = ensure_absolute_path(
                 values.vector_db_url,
             )
-        else:
+        elif not values.vector_db_url:
             # Default path
             databases_directory_path = os.path.join(base_config.system_root_directory, "databases")
             values.vector_db_url = os.path.join(databases_directory_path, "cognee.lancedb")