Fix v1alpha7 e2e tests

The v1alpha7 tests were previously testing v1alpha6.

Author: mdbooth

test/e2e/data/kustomize/v1alpha7/kustomization.yaml

@@ -1,7 +1,7 @@
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
-- ../../../../../kustomize/v1alpha6/external-cloud-provider
+- ../../../../../kustomize/v1alpha7/default
 
 components:
 - ../common-patches/cluster-prev1beta1