crypto/x509: SKID generation is over full spki, rather than just the subjectPublicKey #39429
Description
https://go-review.googlesource.com/c/go/+/227098 introduced automatic SKID generation when one isn't provided using method (1) from RFC 5280 Section 4.2.1.2. The hash provided is over the full SPKI structure, rather than just the subjectPublicKey BIT STRING as defined, which makes it out of line with certain other implementations that assume this is how the SKID is generated.
This is unlikely to break anything major, but if the goal is to use the RFC 5280 method as defined it would make sense to stick to that construction.