... and extend build matrix of libressl.
Most of those new libressl build jobs are marked as `continue: true` since
either they don't build or they cause memory leaks (3.5/OPENBSD_7_1)
The `OPENBSD_X_Y` branches are also marked like that since they will
evolve and maybe break at a later point in time. Currently they represent
the buildable versions of their respective releases (3.3.6 resp. 3.4.3).
Also change CI distro to ubuntu-22.04 as using OpenSSL 3 on 20.04 fails.
Signed-off-by: Steffen Jaeckel <jaeckel-floss@eyet-services.de>
