[Epic] Enable libyui REST in YaST MU
Improve the code maintenance in YaST MU. As we could experience the use of libyui REST is very solid approach in Product validation and now we want to apply it as well for products in maintenance.
The scope is mainly the attended installation as we still didn't have the chance to improve testing of YaST modules in the installed system.
AC1: Attended installation in YaST MU use libyui REST to interact with UI