internal/source: update gitea comment

For golang/go#39559

Change-Id: Id9c2ae0bcac9299565695d79a66f4bf591e60364
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/274956
Trust: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Julie Qiu <julie@golang.org>

internal/source/source.go

@@ -592,8 +592,7 @@ func init() {
 // giteaTransformCommit transforms commits for the Gitea code hosting system.
 func giteaTransformCommit(commit string, isHash bool) string {
 	// Hashes use "commit", tags use "tag".
-	// Short hashes aren't currently supported, but we build the URL
-	// anyway in the hope that someday they will be.
+	// Short hashes are supported as of v1.14.0.
 	if isHash {
 		return "commit/" + commit
 	}