infra_test: fix quoting for labels
infra_test: fix quoting for labels

In prometheus, labels for metrics are quoted.
Fix the lookup we do in testing.

Signed-off-by: Francesco Romani <c7100b580e6017ef67482ace46578cdd2d2e0dfe@redhat.com>

kubevirt/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt,davidvossel/kubevirt,davidvossel/kubevirt,davidvossel/kubevirt,stu-gott/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt