test/k8sT: wrap policy across namespaces test in Context
test/k8sT: wrap policy across namespaces test in Context

This will allow for creation / deletion of resources for this test to be put in `BeforeEach`
and `AfterEach` within said `Context` instead of within the `It` itself.

Signed-off by: Ian Vernon <ian@cilium.io>

scanf/cilium,tklauser/cilium,eloycoto/cilium,michi-covalent/cilium,tklauser/cilium,cilium/cilium,cilium/cilium,eloycoto/cilium,eloycoto/cilium,michi-covalent/cilium,tklauser/cilium,tgraf/cilium,tgraf/cilium,scanf/cilium,michi-covalent/cilium,cilium-team/cilium,scanf/cilium,tgraf/cilium,scanf/cilium,tgraf/cilium,cilium/cilium,tgraf/cilium,eloycoto/cilium,cilium-team/cilium,michi-covalent/cilium,scanf/cilium,scanf/cilium,tklauser/cilium,cilium/cilium,tklauser/cilium,michi-covalent/cilium,scanf/cilium,eloycoto/cilium,cilium/cilium,tgraf/cilium,eloycoto/cilium,eloycoto/cilium