Revise UriEndpointFactory/UriEndpoint

[violetagg]

[yuzawa-san]

I sent off this spring-projects/spring-framework#29954

I'm willing submit a patch to this repo to ideally have the provided URI not have to be reparsed later to generate path and resourcePath. I think I can accomplish this by putting URI inside of the UriEndpoint class. Is that an acceptable solution? A lot of the classes are not public, so think I could do it with no API changes.

[violetagg]

@yuzawa-san Please provide a PR so that we can discuss the changes. Thanks!