Override `Waker::clone_from` to avoid cloning `Waker`s unnecessarily This would be very useful for futures — I think it’s pretty much always what they want to do instead of `*waker = cx.waker().clone()`. Tracking issue: https://github.com/rust-lang/rust/issues/98287 r? rust-lang/libs-api `@rustbot` label +T-libs-api -T-libs