community[patch]: Fix Milvus add texts when ids=None (#17021)

- **Description:** Fix Milvus add texts when ids=None (auto_id=True)

Signed-off-by: Jael Gu <mengjia.gu@zilliz.com>
Co-authored-by: Bagatur <baskaryan@gmail.com>

libs/community/langchain_community/vectorstores/milvus.py

@@ -583,7 +583,9 @@ class Milvus(VectorStore):
             # Grab end index
             end = min(i + batch_size, total_count)
             # Convert dict to list of lists batch for insertion
-            insert_list = [insert_dict[x][i:end] for x in self.fields]
+            insert_list = [
+                insert_dict[x][i:end] for x in self.fields if x in insert_dict
+            ]
             # Insert into the collection.
             try:
                 res: Collection