check_engine_keys: make pass with OpenSSL 3

check_engine_keys: make pass with OpenSSL 3

Not enabled by default with OpenSSL 3, so we don't
see this in our builds.
While here add missing entries to .gitignore (which
is what made me look at engine-key test in the first
place).

Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20230110170257.113527-1-frank@lichtenheld.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg25949.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>
(cherry picked from commit af25448ee19da5d225a6a1f30f26dc3949ed8921)