update github.com/matttproud/golang_protobuf_extensions to 1.0.1
update github.com/matttproud/golang_protobuf_extensions to 1.0.1

This updates github.com/matttproud/golang_protobuf_extensions to a released
version.
There's no significant change in the code itself, and the corresponding
tests (which are not vendored) behave better with vgo (see details in #65683).

Kubernetes-commit: c4244a69e08657baf8660b6b0513e2076baaeb48

kubernetes/kube-aggregator,kubernetes/kube-aggregator