*: reflow comments to 80 characters

This reformats the entire Metropolis codebase to have comments no longer
than 80 characters, implementing CR/66.

This has been done half manually, as we don't have a good integration
between commentwrap/Bazel, but that can be implemented if we decide to
go for this tool/limit.

Change-Id: If1fff0b093ef806f5dc00551c11506e8290379d0
diff --git a/metropolis/pkg/pki/x509.go b/metropolis/pkg/pki/x509.go
index d2affe8..e198902 100644
--- a/metropolis/pkg/pki/x509.go
+++ b/metropolis/pkg/pki/x509.go
@@ -30,12 +30,12 @@
 	unknownNotAfter = time.Unix(253402300799, 0)
 )
 
-// Workaround for https://github.com/golang/go/issues/26676 in Go's crypto/x509. Specifically Go
-// violates Section 4.2.1.2 of RFC 5280 without this.
-// Fixed for 1.15 in https://go-review.googlesource.com/c/go/+/227098/.
+// Workaround for https://github.com/golang/go/issues/26676 in Go's
+// crypto/x509. Specifically Go violates Section 4.2.1.2 of RFC 5280 without
+// this. Fixed for 1.15 in https://go-review.googlesource.com/c/go/+/227098/.
 //
-// Taken from https://github.com/FiloSottile/mkcert/blob/master/cert.go#L295 written by one of Go's
-// crypto engineers
+// Taken from https://github.com/FiloSottile/mkcert/blob/master/cert.go#L295
+// Written by one of Go's crypto engineers
 //
 // TODO(lorenz): remove this once we migrate to Go 1.15.
 func calculateSKID(pubKey crypto.PublicKey) ([]byte, error) {