missing unused_must_use for RPITIT

[lukas-code]

Code

pub trait Tr {
    fn foo() -> impl std::future::Future<Output = ()>;
}

pub async fn bar<T: Tr>() {
    T::foo();
}

Current output

nothing

Desired output

warning: unused implementer of `Future` that must be used
  --> src/lib.rs:10:5
   |
10 |     Tr::foo();
   |     ^^^^^^^^^
   |
   = note: futures do nothing unless you `.await` or poll them
   = note: `#[warn(unused_must_use)]` on by default

Rationale and extra context

No response

Other cases

applies to all #[must_use] traits that are used as RPITIT

Anything else?

No response