Deleting old managed users data

[ahukkanen]

Currently this module only deletes data for users accounts that do not have an email address as specified at:

decidim-module-cleaner/app/jobs/decidim/cleaner/clean_inactive_users_job.rb

Line 18 in 6a396a6

.where.not(email: "")

I think the module should also delete old managed users which do not have an email on their account:
https://github.com/decidim/decidim/blob/3187bdfd40ea1c57c2c12512b09a7fec0b2bed08/decidim-admin/app/controllers/decidim/admin/impersonations_controller.rb#L100-L102

Of course, these users cannot be notified but using the same logic, those users could be marked as "notified" (warning_date) about the deletion the same way and delete those accounts using the same logic as for "regular" users.