Update gnome-boxes to version 42.2 / rev 90 via SR 987358
    
    https://build.opensuse.org/request/show/987358
    by user dimstar + dimstar_suse
    - Update to version 42.2:
      + Ensure spice graphics is specified in vm creation.
      + Recommend openSUSE 15.4.
    - Disable RDP support: glgo#GNOME/gnome-boxes#820):
      + Introduce bcond_with rdp to easily toggle the feature on/off. (forwarded request 987197 from dimstar)