CI: fixes for base image for el8

scripts/ci/images-v2/0001-spack-rhel-fix.patch

@@ -0,0 +1,11 @@
+--- lib/spack/spack/solver/concretize.lp
++++ lib/spack/spack/solver/concretize.lp
+@@ -718,6 +718,9 @@
+ % catalina binaries can be used on bigsur. Direction is package -> dependency.
+ os_compatible("bigsur", "catalina").
+
++os_compatible("rocky8", "centos8").
++os_compatible("centos8", "rocky8").
++
+ % If an OS is set explicitly respect the value
+ node_os(Package, OS) :- node_os_set(Package, OS), node(Package).

scripts/ci/images-v2/Dockerfile.ci-spack-el8-base

@@ -1,4 +1,5 @@
-FROM almalinux/almalinux:8
+ARG BASE_IMAGE=almalinux/almalinux:8
+FROM $BASE_IMAGE
 
 RUN dnf upgrade -y && \
     dnf install -y glibc-langpack-en
@@ -11,12 +12,19 @@ RUN dnf install -y \
         python3 python3-pip
 RUN dnf clean all
 
-RUN git clone https://github.com/spack/spack.git /opt/spack
+RUN git clone -b v0.18.0 https://github.com/spack/spack.git /opt/spack
 COPY packages.yaml.base /etc/spack/packages.yaml
 COPY modules.yaml /etc/spack/modules.yaml
+COPY 0001-spack-rhel-fix.patch /root/0001-spack-rhel-fix.patch
+
+RUN cd /opt/spack && \
+    patch -p0 < /root/0001-spack-rhel-fix.patch
 
 RUN . /opt/spack/share/spack/setup-env.sh && \
+    spack config --scope system add concretizer:targets:granularity:generic && \
+    spack config update modules -y && \
     spack compiler find --scope system && \
-    spack spec zlib && \
     spack clean -a && \
+    spack mirror add E4S https://cache.e4s.io && \
+    spack buildcache keys -it && \
     spack spec zlib

scripts/ci/images-v2/packages.yaml.base

@@ -1,6 +1,6 @@
 packages:
   all:
-    target: [haswell]
+    target: [x86_64]
   cmake:
     variants: ~ownlibs
   adios2: