Relax the version checking for Arch packages (#32908) (#32913)

Backport #32908 by ExplodingDragon

It is mentioned in https://man.archlinux.org/man/PKGBUILD.5: 'The
variable is not allowed to contain colons, forward slashes, hyphens, or
whitespace.'

`_` is also an allowed character, and some software in the Arch Linux
AUR uses this naming convention.

Co-authored-by: Exploding Dragon <explodingfkl@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/packages/arch/metadata.go

@@ -43,8 +43,9 @@ var (
 	ErrInvalidArchitecture = util.NewInvalidArgumentErrorf("package architecture is invalid")
 
 	// https://man.archlinux.org/man/PKGBUILD.5
-	namePattern    = regexp.MustCompile(`\A[a-zA-Z0-9@._+-]+\z`)
-	versionPattern = regexp.MustCompile(`\A(?:[0-9]:)?[a-zA-Z0-9.+~]+(?:-[a-zA-Z0-9.+-~]+)?\z`)
+	namePattern = regexp.MustCompile(`\A[a-zA-Z0-9@._+-]+\z`)
+	// (epoch:pkgver-pkgrel)
+	versionPattern = regexp.MustCompile(`\A(?:\d:)?[\w.+~]+(?:-[-\w.+~]+)?\z`)
 )
 
 type Package struct {