How to insert a record with generated identifiers using UUID()?
One way to vercome the multiple trigger error would be ot use one trigger - and not 4 - to set the new UUID values:

DELIMITER //
CREATE TRIGGER before_insert_on_user_set_uuids
  BEFORE INSERT ON user 
  FOR EACH ROW 
    BEGIN
      SET new.info = replace(uuid(),'-',''); 
      SET new.note = replace(uuid(),'-',''); 
      SET new.auth = replace(uuid(),'-',''); 
      SET new.test = replace(uuid(),'-',''); 
    END ;  //
DELIMITER ;


It would also be good idea to store the UUIDs in BINARY(16) columns instead of VARCHAR(32). Saves 16x4 bytes per row (plus 16 per row multiplied by the number of simple indexes on the columns) and some speed for not considering collations and character sets. And I assume you had the varchar column as ASCII and not UTF-8 which would be a real waste.