automation: stash default config file for artifact extraction

This aids troubleshooting when we notice a failure in the default
configuration.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Doug Goldstein <cardoe@cardoe.com>

.gitlab-ci.yml

@@ -8,7 +8,7 @@ stages:
     - ./automation/scripts/build 2>&1 | tee build.log
   artifacts:
     paths:
-      - xen/.config
+      - xen-config
       - '*.log'
     when: always
   except: