rc6: 2024 edition; upgrade to `cipher` v0.5.0-rc.1 (#510) #929

Job	Run time
build (stable, thumbv7em-none-eabi)	17s
build (1.85.0, thumbv7em-none-eabi)	17s
test (stable)	18s
test (1.85.0)	20s
build (1.85.0, wasm32-unknown-unknown)	20s
build (stable, wasm32-unknown-unknown)	22s
minimal-versions	0s
	1m 54s

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