docs: fix duplicate typedefs

[MrMythicalYT]

Please describe the changes this PR makes and why it should be merged:
This PR fixes duplicate typedefs for GuildForumThreadCreateOptions
Status and versioning classification:

• This PR only includes non-code changes, like changes to documentation, README, etc.

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1 Ignored Deployment

Name	Status	Preview	Updated
discord-js	⬜️ Ignored (Inspect)		Sep 25, 2022 at 11:41AM (UTC)

[jaw0r3k]

Yeah name is confusing
but where u have duplicate? nvm

so I was right like 2 days ago 🥲

[Jiralite]

[codecov]

Codecov Report

Merging #8677 (af295c8) into main (822b7f2) will decrease coverage by 13.21%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##              main    #8677       +/-   ##
============================================
- Coverage   100.00%   86.78%   -13.22%     
============================================
  Files            1       85       +84     
  Lines          822     8773     +7951     
  Branches       154     1109      +955     
============================================
+ Hits           822     7614     +6792     
- Misses           0     1117     +1117     
- Partials         0       42       +42     

Flag	Coverage Δ
builders	100.00% <ø> (?)
collection	100.00% <ø> (ø)
proxy	80.46% <ø> (?)
rest	91.99% <ø> (?)
utilities	100.00% <ø> (?)
voice	63.83% <ø> (?)
ws	60.47% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...actions/slashCommands/mixins/NameAndDescription.ts	100.00% <0.00%> (ø)
packages/voice/src/receive/SSRCMap.ts	86.20% <0.00%> (ø)
packages/builders/src/util/jsonEncodable.ts	100.00% <0.00%> (ø)
packages/proxy/src/handlers/proxyRequests.ts	71.64% <0.00%> (ø)
packages/ws/src/ws/WebSocketManager.ts	95.69% <0.00%> (ø)
packages/builders/src/messages/embed/Embed.ts	100.00% <0.00%> (ø)
packages/voice/src/audio/AudioPlayerError.ts	0.00% <0.00%> (ø)
packages/voice/src/audio/PlayerSubscription.ts	50.00% <0.00%> (ø)
...ashCommands/mixins/ApplicationCommandOptionBase.ts	100.00% <0.00%> (ø)
packages/voice/src/audio/AudioPlayer.ts	80.95% <0.00%> (ø)
... and 74 more

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