weka_upgrade_checker suggestion - Check the size of the stats folder

[galshoham]

If the stats upload is disabled or stats are not uploaded to the cloud for some reason, the stats folder will grow with many files inside.
The folder location:
/opt/weka/data/weka local ps --no-header -o name_weka version current/weka status --json | jq '.guid' | tr -d '"'/stats

The upgrade can fail on timeout while copying the stats from old to the new container.