DefaultClientRequestObservationConvention generates uri tag with incorrect value for a URL of format 'https://server'

[jourteen]

When RestTemplate accesses a URL of format 'https://server' generated http client requests metrics get uri tag of value '/https://server'. I expect correct uri tag's value to be '/'.

A demo application demo.zip is attached. Run it, then check http client requests metrics at http://localhost:8080/actuator/prometheus.

[bclozel]

Closing in favor of #33867