rc5

Bump `cipher` to v0.5.0-rc.6 (#527) #343

Job	Run time
test (1.85.0)	20s
test (stable)	24s
build (1.85.0, thumbv7em-none-eabi)	15s
build (1.85.0, wasm32-unknown-unknown)	19s
build (stable, wasm32-unknown-unknown)	19s
build (stable, thumbv7em-none-eabi)	19s
minimal-versions	0s
	1m 56s

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