Add reference for deleted user

[Elblinator]

resolves #5324
needs [https://github.com/OpenSlides/openslides-autoupdate-service/pull/1274]
and [https://github.com/OpenSlides/openslides-backend/pull/3164]

• csv export missing
• xlsl export missing

[Elblinator]

found by @MSoeb
Deleted users cannot be deleted right now

[MSoeb]

works as intended

[Elblinator]

Waitng for the backend issue/ independent testing OpenSlides/openslides-backend#3164

[luisa-beerboom]

I noticed some relatively minor stuff. If any of my remarks don't work or you don't see them as practival for whatever reason, feel free to tell me

[luisa-beerboom]

Is this even a possible case?
I don't see any new code causing model.getTitle() to display Deleted user (and translated no less), so would this even work?
Also I'd imagine if the getTitle says Deleted user, it must either be a person with a really funny name (who could be treated like any other user) or a motion meeting user link with no attached meeting user, which could therefore not have a user_id

[Elblinator]

Is this even a possible case?

Yes, if a user is deleted (and not removed)
The string is inserted at motion-manage-motion-meeting-users.component.html
Yes it's also translated
this line is only called if the user has no user_id, hence the user is not a "real" user

a motion meeting user link with no attached meeting user, which could therefore not have a user_id

I do not know how to rcreate such a case
I tested it with a user who is not deleted but removed and that user is displayed like before

[Elblinator]

I resolved it?

holidays

[bspekker]

There is an issue after creating a new user in one of the concerned fields: when saving the entry the edit doesn't close and an error will appear when trying to save again.

[luisa-beerboom]

Two minor things