Rollup merge of #57992 - Matthias247:waker4, r=cramertj

Update the future/task API

This change updates the future and task API as discussed in the stabilization RFC at rust-lang/rfcs#2592.

Changes:
- Replacing UnsafeWake with RawWaker and RawWakerVtable
- Removal of LocalWaker
- Removal of Arc-based Wake trait

Author: Centril