replace inherits with class

[jimmywarting]

looking to reduce our sup dependencies, are you willing to accept a PR that switches the code space to newer class \w extend?

[mcollina]

That's not needed. You can replace inherits with https://github.com/nodejs/node/blob/7ca38f05a023666274569343f128c5aed81599f3/lib/internal/streams/writable.js#L70-L71