[master] golang format tools (#2422)
[master] golang format tools (#2422)

Produced via:
  `gofmt -s -w $(find -path './vendor' -prune -o -path './third_party' -prune -o -name '*.pb.go' -prune -o -type f -name '*.go' -print)`
  `goimports -w $(find -name '*.go' | grep -v vendor | grep -v third_party | grep -v .pb.go | grep -v wire_gen.go)`
/assign chaodaig chizhg
/cc chaodaig chizhg
knative/test-infra,knative/test-infra,knative/test-infra