While uploading a torrent, the `announce_list` should be prioritized over the `announce` field

[mickvandijke]

Currently when uploading torrents and then storing the tracker announce urls in database, only the announce field will be stored as tracker url if it is set and announce-list is then ignored. The intended behaviour is that when announce-list is set, it will take priority over the announce field.

MySQL: https://github.com/torrust/torrust-index-backend/blob/develop/src/databases/mysql.rs#L449
SQLite: https://github.com/torrust/torrust-index-backend/blob/develop/src/databases/sqlite.rs#L445