✅ Add status tests

[AlexV525]

Run tests through all HTTP status code.

[AlexV525]

The service always returns 200 when I run these tests locally...

[AlexV525]

https://github.com/golang/go/blob/de5b418bea70aaf27de1f47e9b5813940d1e15a4/src/net/http/server.go#L148-L153

	// The provided code must be a valid HTTP 1xx-5xx status code.
	// Any number of 1xx headers may be written, followed by at most
	// one 2xx-5xx header. 1xx headers are sent immediately, but 2xx-5xx
	// headers may be buffered. Use the Flusher interface to send
	// buffered data. The header map is cleared when 2xx-5xx headers are
	// sent, but not with 1xx headers.