try something to fix the build cache misses

Author: haampie

outputs/init_spack.sh

@@ -1,10 +1,13 @@
-#!/bin/bash
+#!/bin/sh
 
 if [ ! -d ~/spack ]; then
-    git clone --quiet "--branch=$tutorial_branch" --depth=100 https://github.com/spack/spack ~/spack
+    git clone --quiet --branch="$tutorial_branch" --depth=100 https://github.com/spack/spack ~/spack
+    git clone --quiet https://github.com/spack/spack-packages ~/spack-packages
+    (cd ~/spack-packages || exit; git checkout -d "$packages_release")
 fi
 
 cd ~/spack || exit
 . share/spack/setup-env.sh
+spack repo set --destination ~/spack-packages --scope defaults builtin
 # spack tutorial -y
 spack bootstrap now