disable network checks for binary RPMs
    
    Due to excessive network checking (for every RPM file) we now split the
    execution to checking SRPMs and checking all other RPMs. We enable
    network checks only for SRPMs, but not for other RPMs. This does not
    reduce our test coverage, because network checks for SRPMs are a
    superset of network checks for other RPMs, it just lowers the number of
    network requests we do.
    
    The artifact output was slightly adjusted to make it clear that there
    are two separate rpmlint executions. As a bonus, the detail note is now
    much more useful (shows errors and warnings count).
    
    Differential Revision: https://phab.qadevel.cloud.fedoraproject.org/D805