Accept custom filetype-Icons in integrity check

Refering to this [README file](/nextcloud/server/tree/master/themes), I created a theme "myicons" containing this folder: */var/www/nextcloud/themes/myicons/core/img/filetypes/* inside of that Folder I placed some own and aditional filetype icons and maped those Icons to the corresponding files, using the files config/mimetypemapping.json and config/mimetypealiases.json and the commands occ maintenance:mimetype:update-db (to add new defined mimetypes to database) and occ maintenance:mimetype:update-js (to recreate core/js/mimetypelist.js). Works as a charm:  does not pass the integrity check, which results in this anoying error: ![image]( It would be a great improvement if themes would pass the Integrity Check, especially when they are implemented according …