Model Packages not importable after changing Options/Asset Types

### Problem

You can't import a cairis-file if it contains new/different asset types.

### Steps to reproduce:

- Start Cairis-Docker with mysql 8.4 and the latest cairis-docker-containers.
- Create new Database A
- Options/Asset Types: update "Systems" to "System"
- Risk/Assets: Create a new Asset of Type "System"
- System/Export / Model Package (.cairis)
- Create new Database B
- System/Import Model - Pick cairis File.
- You encounter an error message like
[Home](http://servername:7071/)
Import

Error importing /tmpDocker/model.xml: 'Update error (message:(MySQLdb._exceptions.OperationalError) (1048, "Column \'asset_type_id\' cannot be null")\n[SQL: call addAsset(%s,%s,%s,%s,%s,%s,%s,%s)]\n[parameters: (117, \'a\', \'a\', \'a\', \'a\', \'System\', \'0\', \'\')]\n(Background on this error at: https://sqlalche.me/e/20/e3q8))'

Same Problem if you define new asset types instead of updating existing ones.

### Expected behavior

Cairis imports asset types before importing assets and is able to import complete cairis files even if they include different asset types.