Remove suppressions for Wgnu-zero-variadic-macro-arguments (#42136)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/42136

`Wpedantic` flags usage of variadic macros with zero arguments. This is widely supported by different compilers (including MSVC), but was previously forbidden by the standard.

C++ 20 explicitly allows them, so, theoretically Clang should know not to warn about these now. Let's try that.

Changelog: [Internal]

Reviewed By: cortinico

Differential Revision: D52534129

fbshipit-source-id: e27a75081fac6b4196c6dbb5242812877b0bd679