fix weaviate delete_by_ids (#2565)

api/core/rag/datasource/vdb/weaviate/weaviate_vector.py

@@ -150,10 +150,11 @@ class WeaviateVector(BaseVector):
         return True
 
     def delete_by_ids(self, ids: list[str]) -> None:
-        self._client.data_object.delete(
-            ids,
-            class_name=self._collection_name
-        )
+        for uuid in ids:
+            self._client.data_object.delete(
+                class_name=self._collection_name,
+                uuid=uuid,
+            )
 
     def search_by_vector(self, query_vector: list[float], **kwargs: Any) -> list[Document]:
         """Look up similar documents by embedding vector in Weaviate."""