tests: update compatibility tests to use k8s v1.16.2

There is a bug in v1.16.1 and v1.16.0 which causes the API server to
panic when it encounters `x-kubernetes-int-or-string` in a CRD.
So we should test with v1.16.2 or higher instead.

https://github.com/kubernetes/kubernetes/issues/83778

tests/e2e/travis-e2e.sh

@@ -33,7 +33,7 @@ run_e2e_tests() {
     ./kind delete cluster
 }
 
-cluster_compatible_versions=("v1.16.1" "v1.17.0")
+cluster_compatible_versions=("v1.16.2" "v1.17.0")
 
 for cluster_version in "${cluster_compatible_versions[@]}"
 do