Closes: https://github.com/fleetdm/fleet/issues/41799
Changes:
- Added support for a new required meta tag for anonymous case study
articles: `cardTitleForCustomersPage`. The value of this meta tag is
used as the title of the automatically generated card link for the
article on the /customers page.
- Added support for a new meta tag for anonymous case study articles:
`cardBodyForCustomersPage`. If provided, the card link for the article
will use this value for the body text, if not provided, the card link
will display the `articleTitle` meta tag value.
- Updated the /customers page to automatically create card links for
case study articles that have `useBasicArticleTemplate` and
`cardTitleForCustomersPage` meta tags.
