add gitlab-ci job that keeps the gitlab runners' spack up to date with the lab's spack instance

.gitlab-ci.yml

 stages:
   - build
   - deploy
+  - sync
 
 # start an OpenShift Job that will build the Spack environment
 .deploy-build-environment:
@@ -284,3 +285,55 @@ build-spack-env-on-runner:
     paths:
       - .spack-tmp/spack/spack-stage
     when: on_failure
+
+
+sync_gitlab_spack_instance:
+  stage: sync
+  tags:
+    - docker-runner
+    - read-write
+  image: docker-registry.ebrains.eu/tc/ebrains-spack-build-env:gitlab_runners_nfs_latest
+  variables:
+    SPACK_NFS_ENV: ebrains-runner-build
+    SPACK_PATH: /mnt/spack
+    SPACK_USER_CACHE_PATH: $SPACK_PATH/.spack
+    SPACK_USER_CONFIG_PATH: $SPACK_PATH/.spack
+  script:
+    - |
+      if [ ! -d $SPACK_PATH ]; then
+        # git clone --depth 1 -c advice.detachedHead=false  -c feature.manyFiles=true --branch $SPACK_VERSION https://github.com/spack/spack $SPACK_PATH
+        git clone -c feature.manyFiles=true https://github.com/spack/spack $SPACK_PATH
+        cd $SPACK_PATH
+        git checkout -b ebrains_spack_commit a8d440d3ababcdec20d665ad938ab880cd9b9d17
+        cd ../
+        cat <<EOF > $SPACK_PATH/etc/spack/packages.yaml
+      packages:
+        all:
+          target: [x86_64]
+      EOF
+      fi
+    - . $SPACK_PATH/share/spack/setup-env.sh
+    # - spack bootstrap untrust github-actions
+    - spack compiler find
+    - spack compiler list
+    - spack load gcc@10.3.0 || spack install gcc@10.3.0
+    - spack load gcc@10.3.0
+    - spack compiler find
+    - spack compiler list
+    - spack install python@3.8.11 %gcc@10.3.0
+    # - for section in $(spack config list); do spack config blame $section; done
+    - spack repo list | grep -q ebrains-spack-builds && echo "Repository registered already" || spack repo add $CI_PROJECT_DIR
+    - spack repo list
+    - spack env list | grep -q $SPACK_NFS_ENV && echo "Environment created already" || spack env create $SPACK_NFS_ENV $CI_PROJECT_DIR/spack.yaml
+    - spack env activate $SPACK_NFS_ENV
+    - cp $CI_PROJECT_DIR/spack.yaml $SPACK_ROOT/var/spack/environments/$SPACK_NFS_ENV/spack.yaml
+    - spack concretize -f
+    - rm -rf /mnt/build_logs/
+    - spack install --no-check-signature || cp -r /tmp/spack/spack-stage /mnt/build_logs
+  timeout: 1 day
+  only:
+    refs:
+      - schedules
+    variables:
+      - $RELEASE == "experimental"
+  allow_failure: false