Staff semester view course list: Delete button is positioned weirdly

[richardebeling]

The button is rendered below the other buttons without any padding/margin:

As indicated by @niklasmohrin: It's probably a sizing issue of the column, possibly the column should just be wider. (Although, as always, a grow-to-fit behavior might be nice. We talked about columns that grow as required some time ago, don't remember what the consensus there was)

[janno42]

see #1889 for grow-to-fit columns on the text answer review page. the same can be used here.