Fix useless READ MORE markdown
In some cases, the "Read more button" is clearly useless (eg: https://rex.dri.utc.fr/app/university/203/previous-exchanges). Before button click: ![Screenshot_from_2020-04-04_13-00-36](/uploads/07bf1d46f75d9e5b81da75e518543112/Screenshot_from_2020-04-04_13-00-36.png) After button click: ![Screenshot_from_2020-04-04_13-00-46](/uploads/92c2f70c2f6b2f2d90ebed5e9188bf28/Screenshot_from_2020-04-04_13-00-46.png) We need a better heuristic on when to hide the button (and show the whole text) and when to do the opposite.
issue