Design: https://www.figma.com/file/lHqzwSaWfsBiWNj9iyOaoh/plante-UI?node-id=2293%3A29896
When the button is clicked, it should have a spinner inside of it.
When a loading was not caused by the button click, there should be no spinner, the button should disappear immediately (or not appear if it wasn't displayed before).
When the map is scrolled to an already loaded area, the button should disappear, even if it still has the spinner inside.