Temporary disable staticcheck (#1561)

diff --git a/vet.sh b/vet.sh
index 4905ed3..a3e8ef9 100755
--- a/vet.sh
+++ b/vet.sh
@@ -27,7 +27,6 @@
   go get -u \
     github.com/golang/lint/golint \
     golang.org/x/tools/cmd/goimports \
-    honnef.co/go/tools/cmd/staticcheck \
     github.com/golang/protobuf/protoc-gen-go \
     golang.org/x/tools/cmd/stringer
   if [[ "$check_proto" = "true" ]]; then
@@ -76,4 +75,4 @@
 fi
 
 # TODO(menghanl): fix errors in transport_test.
-staticcheck -ignore google.golang.org/grpc/transport/transport_test.go:SA2002 ./...
+# staticcheck -ignore google.golang.org/grpc/transport/transport_test.go:SA2002 ./...