Move to using the tier 3 target

[GnomedDev]

It seems like https://github.com/rust-lang/rust/pull/88991 has merged and there is now a target for the Nintendo Switch, aarch64-nintendo-switch-freestanding. It seems like this project should be using this target now and has intended to in the past once it is merged in https://github.com/aarch64-switch-rs/cargo-nx/blob/f6bd1f4a15e38d6ad900701394745fe92be8ccb9/src/build.rs#L29