Switch to VFS storage driver for more stability

.gitlab-ci.yml

 ---
 variables:
   JOBS: 8
+  STORAGE_DRIVER: 'vfs'
 
 default:
   image: 'quay.io/containers/buildah'
@@ -18,8 +19,8 @@ default:
                    --build-arg FACTER_build=stage1
                    --build-arg FACTER_emerge_default_opts="--jobs=${JOBS} --usepkg"
                    --build-arg FACTER_makeopts="-j${JOBS}"
-                   -v /nest:/nest
                    -v "${PUPPET_CERTIFICATE}:/etc/puppetlabs/puppet/ssl/certs/ci.pem"
                    -v "${PUPPET_PRIVATE_KEY}:/etc/puppetlabs/puppet/ssl/private_keys/ci.pem"
+                   -v /nest:/nest
                    -t "${CI_REGISTRY_IMAGE}:haswell-server" .'
     - 'buildah push --creds="${CI_REGISTRY_USER}:${CI_REGISTRY_PASSWORD}" "${CI_REGISTRY_IMAGE}:haswell-server"'

Containerfile

@@ -4,6 +4,6 @@ FROM nest/stage0:${STAGE0_TAG}
 ARG FACTER_build
 ARG FACTER_emerge_default_opts
 ARG FACTER_makeopts
-RUN puppet agent --test --environment=portage --certname ci --logdir /var/log/puppet --rundir /var/run/puppet --vardir /var/lib/puppet --runtimeout 0; [ $? -eq 2 ]
+RUN puppet agent --test --certname ci --logdir /var/log/puppet --rundir /var/run/puppet --vardir /var/lib/puppet --runtimeout 0; [ $? -eq 2 ]
 
 CMD ["/bin/zsh"]