DOC: Docs describe FAISS get_by_id but it isn't implementd

[sbguthery]

URL

https://python.langchain.com/api_reference/community/vectorstores/langchain_community.vectorstores.faiss.FAISS.html#langchain_community.vectorstores.faiss.FAISS.get_by_ids

Checklist

• I added a very descriptive title to this issue.
• I included a link to the documentation page I am referring to (if applicable).

Issue with current documentation:

Docs for FAISS describe get_by_id but it doesn't seem to be implemented as yet.

Idea or request for content:

I suggest either implementing get_by_id or removing it from the docs.