Skip GitLab MR reply comments

[Half-Shot]

GitLab uses discussion_id to chain together replies. We can't really tell what position we are in the thread, so we just have to assume that if we've not seen the discussion before that we are the first note, and subsequent notes are child notes.

This also changes the code so that we skip sending a notice into the room if the user has disabled comment-only notices.

[jaller94]

Looks good to me.

I'm a bit surprised that Hookshot depends on @alloc/quick-lru instead of the upstream quick-lru (which became an ESM in version 6).

[Half-Shot]

I'm a bit surprised that Hookshot depends on @alloc/quick-lru instead of the upstream quick-lru (which became an ESM in version 6).

We can't use ESM, as it introduces a bunch of annoying incompatibilities. Instead of trying to refactor the entire project to be ESM compatible, we've settled for just using a cJS library for the moment.