Improve typesafety of Snowflake

[jonahsnider]

Please describe the changes this PR makes and why it should be merged:

Since Snowflakes are always numbers in string form, this updates the type to use a template literal type, which will grant TypeScript users safe usage of the type.

Status

• 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

Semantic versioning classification:

• This PR changes the library's interface (methods or parameters added)
  • This PR includes breaking changes (methods removed or renamed, parameters moved or removed)
• This PR only includes non-code changes, like changes to documentation, README, etc.

[vaporoxx]

the typescript dependency needs to be bumped to 4.1

[kyranet]

That... works... I wasn't aware ${number} was a thing:

Only thing though, it allows decimals, but it's still better than nothing. Playground here.

Edit: Playground for ${bigint} for 20cbac9, this solved decimals inside numbers, and seems to forbid the n suffix (which BigInts use).

Once CI's errors are solved, this is good to go.

[jonahsnider]

Fixed by doing ${bigint}!

[NotSugden]

https://github.com/pizzafox/discord.js/blob/cdb6646c9da782461d09a4823924a037aea9f38c/typings/index.d.ts#L2853
this type and possibly others need to be updated to string | Snowflake

a MessageReactionResolvable can also be name:id which does not match `${bigint}`

[ckohen]

Since discord_api_types is now a dependency, this (and many others) could be imports instead

[iCrawl]

This PR is kind of dead anyway, the requested changes weren't made and @vaporox has a bigger typings PR anyway before we release v13 (currently it was closed because the changes would conflict too much with bigger PRs)