Fix the error in e2e test due to the prefix change
Fix the error in e2e test due to the prefix change

The prefix on test namespace was missing so the test was failing.

Tested by running:
     make kind-reset
     make kind-deploy
     k delete validatingwebhookconfigurations.admissionregistration.k8s.io hnc-validating-webhook-configuration
     go test ./e2e/...
All the e2e test passed now.

kubernetes-sigs/multi-tenancy,kubernetes-sigs/multi-tenancy