Add queries to remove organizations

[Riadabd]

Ticket ID

OP-3124 + OP-3125

PR Description

⚠️ DO NOT MERGE INTO DEV OR MASTER!

Once approved, it has to go into a hotfix release as long as the LMB cutover has not been performed yet.

This PR removes unneeded organizations; it is similar to lblod/app-organization-portal#451.

How to Test

If possible, try to run a production backup, run the migrations and inspect the important URIs to see if they have successfully deleted (e.g., bestuurseenheid URI, person + account URIs, conversations + messages + file URIs).

[claire-lovisa]

I don't know how far you want to go but there are also the files such as

  ?fileDataObject a <http://www.semanticdesktop.org/ontologies/2007/03/22/nfo#FileDataObject> ;
    <http://www.semanticdesktop.org/ontologies/2007/01/19/nie#dataSource> ?file .

that don't seem to be deleted here !

[Riadabd]

I remember discussing this with Felix, and I think the idea was to leave these entities intact and only delete ?file ?p ?o. Given that these file data objects contain useful data such as the filename, file size and such, we can use them if we end up implementing something that deletes files completely (both virtual and physical files).

The way we would do it in that case would be to query file data objects that have an empty data source:

  ?fileDataObject a <http://www.semanticdesktop.org/ontologies/2007/03/22/nfo#FileDataObject> ;
    <http://www.semanticdesktop.org/ontologies/2007/01/19/nie#dataSource> ?file .
  
  FILTER NOT EXISTS { ?file ?p ?o }

The results we get are then files that we know were deleted at a previous point in time and can now be safely fully removed from the system.