Upload through quick action menu performs a save

Reproduction steps:

• Edit a page
• type "/" to access quick actions
• type "image"
• select "upload image" and type enter
• select an image and upload it
• click cancel on the editor to leave it

Expected result:

• there's no change at all on the page, no new version in history, no new attachment

Obtained result:

• there's a new attachment and a new version in history