Document wildcard router is fully supported only on OCP version >3.9.27

Wildcard router will only be fully functional hence fully supported on OCP versions higher than 3.9.27. This is because of this fix being introduced in 3.9.27: https://bugzilla.redhat.com/show_bug.cgi?id=1570143

This needs to be called out in user documentation. ideally as an admonition box or similar.