Link from card on contests overview page to single contest page

[vmcj]

The issue suggested using the header only but that felt a bit hard for people to find the link so the whole card is used now. The buttons in the card still work with their own links.

Fixes: #2462

<a href={{ path('jury_contest', {'contestId': contest.cid}) }}>

Is the only interesting piece, the rest is fixing indentation.