72d2c3d Support KojiResolver in MBSResolver.

Authored and Committed by jkaluza 4 years ago
    Support KojiResolver in MBSResolver.
    
    If KojiResolver is enabled for buildrequired base module and
    MBSResolver is used, then `MBSResolver.get_buildrequired_modulemds`
    will use KojiResolver to get the list of buildrequired module builds.
    
    Otherwise it uses the current behavior.
    
    To implement this, the `KojiResolver.get_buildrequired_modules` was
    split into two methods:
    
    - `get_buildrequired_koji_builds` returns buildrequired Koji builds.
    - `get_buildrequired_modules` calls `get_buildrequired_koji_builds`
      and finds the corresponding ModuleBuilds in MBS DB.