Tone down the requirements of a test that will go away.

00-check_testexes.t was a way for me to check that I didn't forget a
compiled test app.  The way it worked was to require MINFO to be present.
Considering the need for this test has diminished considerably at this
point, I might as well tone down the requirement, and have it skip the
test (and not fail it) if MINFO isn't present.

Reviewed-by: Rich Salz <rsalz@openssl.org>