Automate base domain help text on Clusters page

After https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/24580 / https://gitlab.com/gitlab-org/gitlab-ce/issues/52363, the help text on the domain field will vary:

Without ingress	With ingress

But this change will only be visible after the user has refreshed the page. This should be done automatically with the help of Vue