der: impl `RefToOwned`/`OwnedToRef` for `&[u8]`/`Box<[u8]>` #2457

Job	Run time
build (1.65.0, thumbv7em-none-eabi)	2m 48s
build (1.65.0, wasm32-unknown-unknown)	2m 16s
build (stable, thumbv7em-none-eabi)	52s
build (stable, wasm32-unknown-unknown)	1m 1s
test (1.65.0)	2m 57s
test (stable)	1m 35s
minimal-versions / minimal-versions	1m 46s
	13m 15s

Provide feedback