adding the header level

templates/node/node--uw-ct-blog--teaser.html.twig

-{{ dd() }}
 {% include '@components/card/card.twig' with {
   'title': blog.title,
   'date': blog.date,
   'sources': blog.sources,
   'tags': blog.tags,
   'content': blog.content,
+  'header_level': 2,
 } %}