Accidentally double-tapping the "save" button when adding an image

[jeloagnasin]

Accidentally double-tapping the "save" button when adding an image will trigger the save button for that model. But the new image will not be included in the saved model.

This happens when the admin/support staff is a bit impatient with the image upload and tries to click the "save" button again. Or they simply forgot that they already tapped on the "save" button before.

Steps to reproduce:

1. Type in random content.
2. Tap on the add image button.
3. Upload a huge image (to introduce artificial delays).
4. Tap on the "save" button.
5. Immediately tap on the "save" button again.

Expected behavior:

After tapping the "save" button, there should be a loading indicator to let the users know that it is now trying to upload the image.