R1:605210bc95af

Make the chatbot obey the object name blacklist

Summary: Fixes T11508. The config entry `remarkup.ignored-object-names` already contains a blacklist of object names that should be ignored in the web UI. This change makes that blacklist also apply to the chatbot. This makes it possible to have a chatbot ignore things like V1, V2, Q1 and any other phrases the user may not want to generate links to objects.

Test Plan: Create objects (tasks, slowvotes, etc.) then mention the object names in chat (with the…