www/mod_auth_mysql2: Deprecate and set expiration date

Abandoned upstream (1.11 from 2016 was explicitly the final release).
"Require group" authorization is silently non-functional with Apache
2.4, and the SSL option no longer builds against MySQL 8.x. All functionality
is covered by mod_authn_dbd / mod_authz_dbd shipped with Apache itself.

PR: 245911
Sponsored by: Netzkommune GmbH