Modified deletion triggers are not updated in the database

**Describe the bug**
The (deletion) triggers that are set up for the database are only created if they do not yet exist (see also #392).
That also means that if a trigger changes, it is not updated in the database (for example, a new concept is added and it re-uses an enum field, adding to its deletion trigger).
I am not sure how to best address this. Creating the triggers doesn't take _that_ long, so perhaps we should always drop all triggers and recreate them on startup. It would likely be much simpler (and thus less error prone) than verifying if each trigger is modified and only update modified triggers.