crypto/x509: Incorrect documentation for `ParsePKCS8PrivateKey` [1.20 backport]

[gopherbot]

@FiloSottile requested issue #58789 to be considered for backport to the next 1.20 minor release.

Good catch, thank you! @gopherbot please open a backport issue to Go 1.20, this is a confusing documentation bug and it would be nice to get the fix live on pkg.go.dev before the next major release.

[gopherbot]

Change https://go.dev/cl/472415 mentions this issue: [release-branch.go1.20] crypto/x509: fix ParsePKCS8PrivateKey comment

[dmitshur]

No backport needed for Go 1.19 because this issue isn't present in that version.

[gopherbot]

Closed by merging bdd86bd to release-branch.go1.20.