test: replace dns test with known image
test: replace dns test with known image

gcr.io/google_containers/dnsutils:e2e isn't a [known
image](https://github.com/openshift/origin/blob/839dfa9a49e45ccf103e33cedcfff4834b2b3084/test/extended/util/image/README.md)
so dualstack tests are failing the `[sig-arch] Only known images used by tests` test.

akram/origin,mfojtik/origin,gabemontero/origin,deads2k/origin,hroyrh/origin,mfojtik/origin,xiuwang/origin,openshift/origin,mfojtik/origin,bparees/origin,csrwng/origin,soltysh/origin,openshift/origin,deads2k/origin,mahak/origin,jsafrane/origin,hroyrh/origin,hroyrh/origin,coreydaley/origin,sallyom/origin,xiuwang/origin,deads2k/origin,gabemontero/origin,JacobTanenbaum/origin,gabemontero/origin,coreydaley/origin,JacobTanenbaum/origin,sallyom/origin,akram/origin,JacobTanenbaum/origin,xiuwang/origin,soltysh/origin,mahak/origin,sallyom/origin,csrwng/origin,bparees/origin,openshift/origin,csrwng/origin,mahak/origin,jsafrane/origin,coreydaley/origin,soltysh/origin,jsafrane/origin,akram/origin,bparees/origin