mod_wsgi overhaul
    
    In CentOS Stream, python3-mod_wsgi no longer provides mod_wsgi, so ask
    for the package name directly.  This is part of an upcoming 8.2 update.
    This change also does some related cleanup.
    
    * un-nest the main code from the skip conditions
    * remove service control from the installation script
    * utilize str.encode() to get the correct string type on either py2 or py3
    * use systemctl where appropriate
    * remove files when done
    
    https://git.centos.org/rpms/mod_wsgi/c/4a746b53e9e3fef74b227e016e785449160871b8?branch=c8s
    https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8-beta/html-single/8.2_release_notes/index#enhancement_dynamic-programming-languages-web-and-database-servers