fix(Guild): Widget channel types and fixes

[Jiralite]

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

1. Upon receiving a guild from Discord, I noticed Guild#widgetEnabled and Guild#widgetChannelId did not exist. This was documented as potentially missing, so a null fallback has been added.
2. A widget channel can actually be more than a text channel. It can be an announcement channel, a voice channel and a stage channel too. Any other channel type returns an API error from Discord.

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

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1 Ignored Deployment

Name	Status	Preview	Updated
discord-js	⬜️ Ignored (Inspect)		Aug 21, 2022 at 9:24AM (UTC)

[codecov]

Codecov Report

Merging #8530 (a76bd65) into main (8028813) will increase coverage by 7.72%.
The diff coverage is n/a.

❗ Current head a76bd65 differs from pull request most recent head 162b94b. Consider uploading reports for the commit 162b94b to get more accurate results

@@            Coverage Diff             @@
##             main    #8530      +/-   ##
==========================================
+ Coverage   78.73%   86.45%   +7.72%     
==========================================
  Files          22       87      +65     
  Lines        3503     8462    +4959     
  Branches      320     1105     +785     
==========================================
+ Hits         2758     7316    +4558     
- Misses        741     1103     +362     
- Partials        4       43      +39     

Flag	Coverage Δ
builders	100.00% <ø> (?)
collection	100.00% <ø> (?)
proxy	73.28% <ø> (?)
rest	92.53% <ø> (ø)
utilities	100.00% <ø> (?)
voice	64.08% <ø> (?)
ws	59.57% <ø> (ø)

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

Impacted Files	Coverage Δ
packages/voice/src/audio/AudioPlayer.ts	80.55% <0.00%> (ø)
packages/voice/src/receive/SSRCMap.ts	86.20% <0.00%> (ø)
packages/voice/src/util/entersState.ts	100.00% <0.00%> (ø)
...s/src/interactions/slashCommands/options/number.ts	100.00% <0.00%> (ø)
...s/builders/src/components/selectMenu/SelectMenu.ts	100.00% <0.00%> (ø)
packages/builders/src/util/validation.ts	100.00% <0.00%> (ø)
packages/voice/src/util/Secretbox.ts	33.33% <0.00%> (ø)
packages/builders/src/components/Assertions.ts	100.00% <0.00%> (ø)
packages/voice/src/joinVoiceChannel.ts	100.00% <0.00%> (ø)
packages/voice/src/networking/VoiceUDPSocket.ts	90.47% <0.00%> (ø)
... and 55 more

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