Stop using application-periodic-default-gke job

[spiffxp]

Related:

• Part of: https://github.com/kubernetes/test-infra/issues/23778

The job should be migrated to not depend on proprietary/hosted clusters, and instead use a cluster that is provisioned by open source software, e.g.

• kubernetes/kops
• kubernetes-sigs/kind
• kubernetes/kubernetes/cluster/kube-up.sh

The job is currently continuously failing, so if it's not actively being used, another option is to delete it entirely, ref: https://testgrid.k8s.io/sig-apps#application-periodic-default-gke

[spiffxp]

Based on https://github.com/kubernetes-sigs/application/pull/138 I'm going to assume the job is safe to remove

[spiffxp]

/assign