Summary
Currently the sweep server isn't being tested in test/format. The reason is because of the default values set for the file manager WT configuration.

    Config('file_manager', '', r'''
        control how file handles are managed''',
        type='category', subconfig=[
        Config('close_handle_minimum', '250', r'''
            number of handles open before the file manager will look for handles to close''',
            min=0),
        Config('close_idle_time', '30', r'''
            amount of time in seconds a file handle needs to be idle before attempting to close
            it. A setting of 0 means that idle handles are not closed''',
            min=0, max=100000),
        Config('close_scan_interval', '10', r'''
            interval in seconds at which to check for files that are inactive and close them''',
            min=1, max=100000),
        ]),

Test/format can only open up to 32 tables at once, thus making the sweep server not needing to do anything until 250 tables are open. Another interesting configuration to play around with is close_idle_time where the dhandle needs to be idle for 30 seconds before deciding to close it. Test/format will very rarely allow that to happen as it performs operations on all the tables quite consisently.

Therefore the aim of this ticket is to allow this to be randomly configured by test/format such that we have interaction of sweep server. The developer will need to add mainly close_idle_time and close_handle_minimum connection configurations to be generated by test/format and check if there are any new WT fallouts.