Allow using Pagure with python-redis >= 3.0.0
    
    There doesn't seem to be any issues when running the test suite locally
    with python-redis >= 3.0.0, so let's allow it again.
    
    Fixes: https://pagure.io/pagure/issue/4183
    
    Signed-off-by: Neal Gompa <ngompa13@gmail.com></ngompa13@gmail.com>