fix: support new voice encryption modes

[NeloBlivion]

Summary

Discord, in all their wisdom, decided to deprecate old encryption modes and have them removed in the span of 3 months.
Untested, please help

Information

• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed).
• This PR is not a code change (e.g. documentation, README, typehinting,
  examples, ...).

Checklist

• I have searched the open pull requests for duplicates.
• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• If type: ignore comments were used, a comment is also left explaining why.
• I have updated the changelog to include these changes.

[Icebluewolf]

What about aead_aes256_gcm_rtpsize?

[NeloBlivion]

unlikely target for this PR, aead_xchacha20_poly1305_rtpsize was chosen for it's similarity to the existing methods and ease in switching over (alongside being required, while aead_aes256_gcm_rtpsize is optional)

[JustaSqu1d]

#2644 is potentially related? (I have no idea how voice works)

[Icebluewolf]

#2644 is potentially related? (I have no idea how voice works)

Pretty sure no, it should error when it can't find an encryption type of it was related to this. It is able to successfully choose a voice type. Also, I think the problem is no one knows that much about voice XD