tests, kubernetes: drop function signature comment
tests, kubernetes: drop function signature comment

Comments are evil - they are bound to rot. Drop the rotten comment which
refers to a non-existing argument `since`. The next commit is going to
simplify the function and make the comment redundant.

Signed-off-by: Dan Kenigsberg <184831158ae7531bcabc22617ed51e8717c81e93@redhat.com>

kubevirt/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt