fix submitButton() @ Builder.php
fix submitButton() @ Builder.php

"save" for "MODE_EDIT" and "submit" for others (just for "MODE_CREATE")
z-song/laravel-admin,qq447665722/laravel-admin,never615/laravel-admin,qq447665722/laravel-admin,qq447665722/laravel-admin,never615/laravel-admin,z-song/laravel-admin