Add a type of calculated field that is Proxy Means Test

[gonzalesedwin1123]

This should be a valid SQL formula so it can be easily re-calculated. This field is calculated after the criteria fields.

[github-actions[bot]]

There hasn't been any activity on this issue in the past 6 months, so it has been marked as stale and it will be closed automatically if no further activity occurs in the next 30 days. If you want this issue to never become stale, please ask a PSC member to apply the "no stale" label.

[celinenilla]

This ticket is now tracked in https://projects.acn.fr/wp/255