fix: crop crash confirm button always disabled

Author: michaellyu

src/vue-core-image-upload.vue

@@ -234,9 +234,9 @@
  },
 
  __setUpload(btn) {
- btn.value = btn.value + '...';
- btn.disabled = true;
  const upload = (code) => {
+ btn.value = btn.value + '...';
+ btn.disabled = true;
  this.tryAjaxUpload(() => {
  btn.value = btn.value.replace('...','');
  btn.disabled = false;