Http::Response.build passing nil status code to HTTP::Response.new

[trapped]

Here the status code is allowed to be nil, causing the compiler to complain:

in ./libs/amethyst/amethyst/base/handler.cr:12: instantiating 'Amethyst::Http::Response#build()'
        response.build
                 ^~~~~
in ./libs/amethyst/amethyst/http/response.cr:23: instantiating 'HTTP::Response:Class#new((Nil | Int32), String, HTTP::Headers)'
        return HTTP::Response.new(@status, @body, headers = @headers)
                              ^~~
instantiating 'HTTP::Response#initialize((Nil | Int32), String, HTTP::Headers, Nil, String, Nil)'
in /Users/giorgio/Documents/crystal/src/http/response.cr:14: instantiating 'HTTP::Response:Class#mandatory_body?((Nil | Int32))'
    if Response.mandatory_body?(@status_code)
                ^~~~~~~~~~~~~~~
in /Users/giorgio/Documents/crystal/src/http/response.cr:77: undefined method '/' for Nil (compile-time type is (Nil | Int32))
    !(status_code / 100 == 1 || status_code == 204 || status_code == 304)

Either Http::Response.new should not allow a nil status code, or Http::Response.build should check for that and use a "default" one.