Address issues found by new pylint 2.5.0
    
    * fix multiple exception-escape
    * fix function signatures of DsInstance start/stop/restart
    * silence f-string-without-interpolation
    * fix too-many-function-args in host plugin
    
    Fixes: https://pagure.io/freeipa/issue/8297
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Stanislav Levin <slev@altlinux.org>