Follow-up of !6977
I was fooled by the fact that for SQLite the columns corresponding to `string` fields were created as `TEXT`; but this is not the case for PostgreSQL and MariaDB/MySQL. According to XORM default mapping rules[^1] _String is corresponding to varchar(255)_.
Therefore `abuse_report`.`remarks` should be of type `VARCHAR(500)` and `abuse_report_shadow_copy`.`raw_value` of type `LONGTEXT`.
### Testing
I have dropped the affected columns (or the entire tables) and checked that for PostgreSQL and MariaDB they are created with the correct type and also manually tested the abusive content reporting functionality in order to make sure that no DB error will be returned if for 'Remarks' a text longer than 255 characters is submitted or when a (big) shadow copy is created.
[^1]: https://xorm.io/docs/chapter-02/4.columns/
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/8267
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: floss4good <floss4good@disroot.org>
Co-committed-by: floss4good <floss4good@disroot.org>