CI: Spack v0.21.1

Update Spack in CI to the latest stable release.

Author: ax3l

Diff for: .github/workflows/dependencies/install_spack

@@ -3,7 +3,7 @@
 
 set -eu -o pipefail
 
-spack_ver="0.17.1"
+spack_ver="0.21.1"
 
 cd /opt
 if [[ -d spack && ! -f spack_${spack_ver} ]]

Diff for: .github/workflows/tooling.yml

@@ -20,6 +20,9 @@ jobs:
       run: |
         sudo apt-get update
         sudo apt-get install clang clang-tidy gfortran libopenmpi-dev python
+
+        which cmake
+
         sudo .github/workflows/dependencies/install_spack
     - name: Build
       env: {CC: clang, CXX: clang++}