gitlab-CI: Stop installing openssl packages

As we stopped using them in 70749c70 ("tests: drop openssl
dependency in favor of glib sha1 implementation"), stop using them in gitlab.

Signed-off-by: Petri Latvala <petri.latvala@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>