Adding links to the quickstart projects so that they can be easily found by readers.
Based it off from the Authorization Services document where it lists authorization quickstart projects.
Related to keycloak/keycloak#10279
Co-authored-by: andymunro <48995441+andymunro@users.noreply.github.com>
Co-authored-by: Hynek Mlnařík <hmlnarik@users.noreply.github.com>