Add option to disable warnings printed from macro during build

[ssnover]

We're making use of this crate for generating typescript types for communication with a TS application and it functions great! I've recently been cleaning up warnings across the codebase and came across these warnings:

warning: failed to parse serde attribute
  | 
  | #[serde(deny_unknown_fields)]
  | 
  = note: ts-rs failed to parse this attribute. It will be ignored.

Since it looks like they're generated internal to the macro by printing to the console, there is no way to turn them off and they spam repeatedly. It'd be nice if these could be opt-out with a feature or something as there isn't enough information to do anything about the warning (no line number, struct name) and I suspect that they're outside our source as well.

[rcvfdmark]

I have a fork of this change, which it turns out is trivial.

[escritorio-gustavo]

This was implemented in #185, and the feature flag was renamed to no-serde-warnings in #189 with a small oversight that was fixed in #191

Just add this to your Cargo.toml

[dependencies]
ts-rs = { version = "7.1.1", features = ["no-serde-warnings"] }

[NyxCode]

Let's hope #54140 comes around soon, so we can do this properly!