pkcs8

x509-cert: use `SubjectPublicKeyInfoOwned::from_key` (#1271) #2685

Job	Run time
build (1.65.0, thumbv7em-none-eabi)	4m 33s
build (1.65.0, wasm32-unknown-unknown)	5m 46s
test (1.65.0)	8m 2s
build (stable, thumbv7em-none-eabi)	45s
test (stable)	3m 24s
build (stable, wasm32-unknown-unknown)	42s
minimal-versions / minimal-versions	2m 54s
	26m 6s

Provide feedback