TL;DR Milvus regression in LangChain v0.1.5

A recent regression in Milvus has caused an error when using Langchain v0.1.5 to connect with it, specifically a "KeyError: 'pk'" error due to the absence of an automatically generated primary key field. The temporary solution is to downgrade to Langchain version <= v0.1.4 until the fix is officially merged. A permanent solution will be provided in an upcoming update that addresses this issue by handling cases where "pk" is not present during insertion. Until then, users can workaround the problem by downgrading their Langchain version or waiting for the official fix.