devel::squashfs-tools: fix download URL

The download URL used before recreates the archive on every download
using `git-archive` in the background. This includes a version hash
which changes it's length depending on the number of commits in the
repository and thus the digest of the archive.

See
BobBuildTool#112 (comment).

Author: rhubert

recipes/devel/squashfs-tools.yaml

@@ -16,7 +16,7 @@ depends:
 
 checkoutSCM:
     scm: url
-    url: ${GITHUB_MIRROR}/plougher/squashfs-tools/archive/${PKG_VERSION}.tar.gz
+    url: ${GITHUB_MIRROR}/plougher/squashfs-tools/releases/download/${PKG_VERSION}/squashfs-tools-${PKG_VERSION}.tar.gz
     digestSHA256: "94201754b36121a9f022a190c75f718441df15402df32c2b520ca331a107511c"
     stripComponents: 1