tests/utils: declare callUrlOnPod as private
tests/utils: declare callUrlOnPod as private

Nothing uses callUrlOnPod outside utils; make this clearer to a reader
who may want to modify it.

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

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