internal/rosa/libxml2: fetch source tarball

This does not have submodules, so the overhead of git is unnecessary.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/libxml2.go

@@ -5,10 +5,11 @@ import "hakurei.app/internal/pkg"
 func (t Toolchain) newLibxml2() (pkg.Artifact, string) {
 	const (
 		version  = "2.15.3"
-		checksum = "oWkNe53c3d4Lt4OzrXPHBcOLHJ3TWqpa0x7B7bh_DyZ-uIMiplpdZjQRgRWVal2h"
+		checksum = "oJy74htGlEpf70KPvpW18fYJo0RQQkCXZRwqUz6NoXborS3HCq3Nm4gsyaSeNmUH"
 	)
-	return t.NewPackage("libxml2", version, t.newTagRemote(
-		"https://gitlab.gnome.org/GNOME/libxml2.git",
+	return t.NewPackage("libxml2", version, newFromGitLab(
+		"gitlab.gnome.org",
+		"GNOME/libxml2",
 		"v"+version, checksum,
 	), &PackageAttr{
 		// can't create shell.out: Read-only file system