Add clone method in `Request`

[Jeevanandam M.]

Discussed in #588

^{Originally posted by shotamakino October 11, 2022}
Hi, thank you for this great package!

I am trying to clone a Request instance in order to reuse it again with a different set of query parameters (for pagination). I was wondering if there's some kind of support for a Clone method similar to https://pkg.go.dev/net/http#Request.Clone?