Remove html tables in favor of grid system

[jeriox]

          We should really avoid introducing new html tables in templates. We should redesign this using bootstraps grid system and implement it for pages and qualifications as well, possibly including functionality for sorting/filtering like the datalist we once had. I'd be fine with moving this to an extra issue.

Originally posted by @felixrindt in https://github.com/ephios-dev/ephios/pull/1361#discussion_r1797703075