[Feature Request]: Wrapper API request body formed into JSON format

[MattMoszczynski]

Feature Description

I have notied that bodies of each request sent to UPS API are formed into XML fomat, but looking through latest documentation of UPS API it suggests to send body requests in JSON format. I think this also cause a The request is well formed but the request is not valid (10002) error getting thrown whenever I try to use the wrapper. Would it be possible in the future to add functionality for wrapper to form requests body in JSON format?

Is this feature valuable for other users as well and why?

The UPS API has changed and will be changing. XML format is also getting slowly replaced with JSON format. I believe it's important to implement JSON based requests for the wrapper.

[rawilk]

This is definitely something that should be done to this package at some point. I'm personally using EasyPost to ship packages now, so I'm not really using this package in my own projects anymore so I'm not sure when I'll have a chance to work on that.