replace bash with sh

.gitlab-ci.yml

@@ -38,7 +38,8 @@ create-vps:
   script:
     - echo "hostname $HOSTNAME, subdomain $SUBDOMAIN, domain $DOMAIN, address $ADDRESS";
     - ls clusters/${HOSTNAME} || echo "directory clusters/${HOSTNAME} not found"
-    - bash .gitlab/ci_scripts/create_vps.sh
+    # Creates the VPS only if an old VPS for this branch is not re-usable
+    - sh .gitlab/ci_scripts/create_vps.sh
   artifacts:
     paths:
     - clusters