fix: Specify required argument types for variadic functions

[mattabullock]

Summary

On arm64 macOS, variadic functions have special calling rules. In pycord the correct argument types have to be specified so ctypes can pass them correctly.

Apple docs: https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms#Update-Code-that-Passes-Arguments-to-Variadic-Functions

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.