Fix dates described by data instead of date

_includes/cards/post_card.html

_includes/cards/post_card_image.html

...20/03/2020-03-13-jsc-hpc-support-for-covid-19-research.md

_posts/2020/04/2020-04-06-hifis-support-folding-at-home.md

...08-kit-supports-distributed-protein-computing-projects.md

...ts/2020/04/2020-04-15-hifis-software-workshops-in-2020.md

_posts/2020/05/2020-05-15-guidelines-for-chatting.md

...s/2020/05/2020-05-15-guidelines-for-video-conferencing.md

_posts/2020/05/2020-05-27-sab-summary.md

...ts/2020/06/2020-06-01-hifis-software-helpdesk-launched.md

_posts/2020/06/2020-06-19-hifis-in-the-egi-newsletter.md

.../06/2020-06-26-guidelines-for-collaborative-notetaking.md

_posts/2020/07/2020-07-08-haicore-kit.md

_posts/2020/07/2020-07-24-helmholtz-aai.md

_posts/2020/07/2020-07-31-hip-hmc-calls.md

_posts/2020/08/2020-08-03-HZI.md

_posts/2020/08/2020-08-10-sp-last-iteration.md

_posts/2020/09/2020-09-01-VPN.md

_posts/2020/09/2020-09-16-hifis-homepage-helpdesk.md

_posts/2020/10/2020-10-13-initial-service-portfolio.md