Add extra disks to postgres primary on staging
Add extra disks to postgres primary on staging

Two extra disks - one for data and one for backup to take into account
the extra data we expect to generate from Email Alert Api.

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet