UnsupportedWarning: Status message is not supported by HTTP/2 (RFC7540 8.1.2.4)
Hi
I tried to use the koa 2.5.3 framework on http2, but when the client accesses a url that does not exist, it will trigger the "UnsupportedWarning: Status message is not supported by HTTP/2 (RFC7540 8.1.2.4)" warning.
This seems to be because koa is set or gets [response.statusMessage](https://nodejs.org/dist/latest-v10.x/docs/api/http2.html#http2_response_statusmessage)[Related source code](https://github.com/nodejs/node/blob/master/lib/internal/http2/compat.js#L550)

Is there any way to solve it?