fix: Nested new call problem

[usualoma]

fixes #104

Cause of the Problem

This is a bit of a detour, but the cause is that when new Response(options) was called in a nested manner, the options referred to the same object in memory as the parent and child.

So when we did this.#res.headers.delete('content-type') at the following location in hono, all content-types of the parent and child were deleted and the applicatioin/json information was lost.

https://github.com/honojs/hono/blob/main/src/context.ts#L145

If the actual global.Response is passed to option when making a nested new call, the header is cloned in it process, so this problem is fixed.

[yusukebe]

@usualoma

LGTM! Thanks for the quick fix!