Fix MacOS build tests (#17542)

* MacOS build tests

- Run on PR that modify the YAML file of the workflow
- Don't clone Spack, since we are in the Spack repo now

* Try to add opengl to configuration to build jupyter

* fixup

.github/workflows/install_spack.sh

@@ -1,5 +1,20 @@
 #!/usr/bin/env sh
-git clone https://github.com/spack/spack.git
-echo -e "config:\n  build_jobs: 2" > spack/etc/spack/config.yaml
-. spack/share/spack/setup-env.sh
-spack compilers
+. share/spack/setup-env.sh
+echo -e "config:\n  build_jobs: 2" > etc/spack/config.yaml
+spack config add "packages:all:target:[x86_64]"
+# TODO: remove this explicit setting once apple-clang detection is fixed
+cat <<EOF > etc/spack/compilers.yaml
+compilers:
+- compiler:
+    spec: apple-clang@11.0.3
+    paths:
+      cc: /usr/bin/clang
+      cxx: /usr/bin/clang++
+      f77: /usr/local/bin/gfortran-9
+      fc: /usr/local/bin/gfortran-9
+    modules: []
+    operating_system: catalina
+    target: x86_64
+EOF
+spack compiler info apple-clang
+spack debug report