fix handle native glpi dropdown types when binding additional field to form destination

[Herafia]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

• It fixes !45483
• Fixes the submission of a form containing an additional field of the native glpi dropdown type (e.g : Groups) linked to a destination. The raw response (itemtype/items_id array) was inserted into the database, causing an SQL error and an error when rendering the response.
  We now extract the items_id for all dropdown types, and the id is cast to int before being read.