As a **fundraising service team member**,
**I want** have incoming emails categorized automatically,
**so that** I can prioritize better.
Acceptance Criteria:
* The contact form provides a select field containing options of general topics to choose from.
* Users can only pick one of the entries.
* The selected topic is sent as part of the content body as follows: `Thema: {{value}}`.
* The label of the field says "" and is positioned below the subject field.
* No value is preselected.
* The newly added field is mandatory.
Background:
Visitors of our donation application use the contact form pretty often. The system processing the incoming requests is capable of categorizing based on several conditions, (e. g. content body). Providing users with an additional field for categorization of their request enables us to filter incoming requests based on that information.