Measure conversion time for UUri->Zenoh Key and optimize if needed

[gregmedd]

          as this code will be called each time send is called, do you know if there is any performance impact?

Originally posted by @MelamudMichael in #23 (comment)

As observed, this code will be called a lot. It should be measured and optimized. However, a significant refactor is pending with the expected 1.5.8 spec update; the micro serialization will be replaced with short-form serialization. As such, we should probably wait until that change to evaluate performance.