Add packet_ubuntu20-calico-aio-hardening (#9359)

To verify the hardening method works always.
The configuration comes from docs/hardening.md

Fix yaml format of hardening.yml

Add condition to skip 040 test for hardening

.gitlab-ci/packet.yml

@@ -51,6 +51,11 @@ packet_ubuntu20-aio-docker:
   extends: .packet_pr
   when: on_success
 
+packet_ubuntu20-calico-aio-hardening:
+  stage: deploy-part2
+  extends: .packet_pr
+  when: on_success
+
 packet_ubuntu18-calico-aio:
   stage: deploy-part2
   extends: .packet_pr