Include pkgrel in the local source filename

Artifact rebuilds (e.g. dependency bundling) change the file behind
<pkg>-<ver>.tar.zst while keeping its name, so users with the previous
file in their AUR helper cache hit a checksum mismatch. Naming the local
download <pkg>-<ver>-<rel>.tar.zst makes every rebuild a fresh file.

snapx-bin/.SRCINFO

@@ -12,7 +12,7 @@ pkgbase = snapx-bin
 	conflicts = snapx-ui
 	options = !strip
 	options = !debug
-	source = https://github.com/Felitendo/PKGBUILDS/releases/download/snapx-bin-0.4.0/snapx-bin-0.4.0.tar.zst
+	source = snapx-bin-0.4.0-1.tar.zst::https://github.com/Felitendo/PKGBUILDS/releases/download/snapx-bin-0.4.0/snapx-bin-0.4.0.tar.zst
 	sha256sums = d2098cac542bca82e68be0a4fa98db22f2d84d35c683d18582382dc9206eb5ee
 
 pkgname = snapx-bin