[BUG] feat(context): update request before calling next

[tigerwill90]

When a wrapped http.Handler middleware replace the request, WrapM does not update the context request before calling next.

func TestWrapM(t *testing.T) {
	wrapped := WrapM(func(handler http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
                        // clone and update the request
			req := r.Clone(r.Context())
			req.Header.Set("foo", "bar")
                        // call the next handler with the new request
			handler.ServeHTTP(w, req)
			_, _ = w.Write([]byte("fox"))
		})
	})
	invoked := false

	w := httptest.NewRecorder()
	r := httptest.NewRequest(http.MethodGet, "https://example.com/foo", nil)

	fox := New(WithMiddleware(wrapped))
	fox.MustHandle(http.MethodGet, "/foo", func(c Context) {
                 // We should have the cloned request
		assert.Equal(t, "bar", c.Header("foo"))
		invoked = true
	})

	fox.ServeHTTP(w, r)
	assert.Equal(t, "fox", w.Body.String())
	assert.True(t, invoked)
}