fix: normalize urls for config

[PHOL-DA]

Problem
Some times people expect default behavior when inserting string urls in config, for instance they might insert localhost:8080 instead of http://localhost:8080 or they might insert my-domain.com instead of http://my-domain.com.

Solution
This pr addresses default behavior, defined as:

• if using http and no port, then use port 80
• if using https and no port, then use port 443
• if no transport is provided use http