component-400: interactions widget cuts off the rightmost column.

We've had an issue reported where the right-hand edge of cells are truncated in certain scenarios. I think this is to do with the long table headers on the leftmost cell.

See https://github.com/intermine/intermine/issues/2188 where this was originally reported.
 - in this image the numbers on the right are cut off!

on my laptop on firefox it's even worse - the matches column doesn't even show up:

My suggestion - give the top left table header cell a maximum width.

This might be a css-only fix - we'll need to update this file: https://github.com/intermine/intermine-apps-c/blob/master/component-400/src/app.styl