tests: add testcli reference in/out & do DejaGNU

This adds reference in & output for the previously added testcli tool,
to check basic CLI parsing/help functions.  Unlike "testcommands", this
one doesn't depend on compile-time system details.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/tests/libzebra.tests/Makefile.am b/tests/libzebra.tests/Makefile.am
index 819cce2..4b74e2d 100644
--- a/tests/libzebra.tests/Makefile.am
+++ b/tests/libzebra.tests/Makefile.am
@@ -2,4 +2,5 @@
 	tabletest.exp \
 	test-timer-correctness.exp \
 	testcommands.exp \
+	testcli.exp \
 	testnexthopiter.exp