Repository Set enablement page needs to handle unsupported repo types better
On a katello instance without ostree support,
1) Import a manifest (recent one)
2) Go to RedHat Repositories screen
3) Notice the ostree tab. Click on it
Either No ostree tab, or an ostree tab with a nice error message "This is not a supported type. You need to enable ostree to use this feature. Notice OSTree is only supported on RHEL 7"
Notice that it even shows you check box for enablement and fails when you click on it.