feat(Threads): max autoArchiveDuration option

[papsavas]

Please describe the changes this PR makes and why it should be merged:
This adds a "MAX" option to ThreadAutoArchiveDuration that sets a thread's auto-archive duration to the maximum one, based on the guilds boost count.

I understand that this is not really needed, so here's a couple of reasons this may or should get rejected:

• Runtime check
• Changes ThreadAutoArchiveDuration type to number | string (could be solved by setting all options to string and converting later)
• Can be defined from moderators using channel default archived duration

Status and versioning classification:

• Code changes have been tested against the Discord API, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating
• This PR changes the library's interface (methods or parameters added)

[kyranet]

Maybe we can make a new method in Util to fetch the highest duration available for a guild, but otherwise this is fine.

Stale

[vladfrangu]

I'd really love to see this filtering get moved to a util function, but LGTM I suppose