NotesDashboard doesn't work with other entity types

[sleidig]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Configure an entity widget like this:

{
  "component": "NotesDashboard",
  "config": {
    "sinceDays": 28,
    "fromBeginningOfWeek": false,
    "mode": "with-recent-notes",
    "entity": "School"
  }
}

Expected behavior
This should list entities linked to "School" entities but it still shows "Children with new notes"

--> make properly work for any entity type.

also: We use "entityType" rather than "entity" for this kind of config property usually.