feat: add button download and test file on metadata type detail page

...ta-type-form/admin-metadata-type-form.presentational.html

...ta-type-form/admin-metadata-type-form.presentational.scss

...data-type-form/admin-metadata-type-form.presentational.ts

...detail-edit/admin-metadata-type-detail-edit.routable.html

...e-detail-edit/admin-metadata-type-detail-edit.routable.ts

.../admin/metadata-type/stores/admin-metadata-type.action.ts

...s/admin/metadata-type/stores/admin-metadata-type.state.ts

...-toolbar-detail/button-toolbar-detail.presentational.html

src/assets/i18n/de.json

src/assets/i18n/en.json

src/assets/i18n/fr.json