header.go
func (h *RequestHeader) DelAllCookies() {
	h.parseRawHeaders()
	h.collectCookies()
	h.cookies = h.cookies[:0]
}
func (h *RequestHeader) DelAllCookies() {
	h.parseRawHeaders()
	h.collectCookies()
	h.cookies = h.cookies[:0]
}
// DelAllCookies removes all the cookies from request headers.