Merge pull request #6627 from nextcloud/icon-on-apps-settings

core/css/icons.scss

core/img/actions/close.svg

core/img/categories/auth.svg

core/img/categories/bundles.svg

core/img/categories/customization.svg

core/img/categories/files.svg

core/img/categories/integration.svg

core/img/categories/monitoring.svg

core/img/categories/multimedia.svg

core/img/categories/office.svg

core/img/categories/organization.svg

core/img/categories/social.svg

settings/js/apps.js

settings/templates/apps.php