Fix csv upload (#13835)

config/initializers/paperclip.rb

@@ -111,3 +111,5 @@ else
     url: ENV.fetch('PAPERCLIP_ROOT_URL', '/system') + '/:prefix_url:class/:attachment/:id_partition/:style/:filename',
   )
 end
+
+Paperclip.options[:content_type_mappings] = { csv: Import::FILE_TYPES }