Bump `cipher` dependency to v0.5.0-pre.2 #107

Job	Run time
build (1.65.0, thumbv7em-none-eabi)	1m 46s
build (1.65.0, wasm32-unknown-unknown)	1m 49s
test (1.65.0)	1m 57s
build (stable, thumbv7em-none-eabi)	14s
test (stable)	30s
build (stable, wasm32-unknown-unknown)	14s
minimal-versions / minimal-versions	28s
	6m 58s

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