Return non zero code on failure

tests/test_cli.py

@@ -7,7 +7,7 @@ from bioflow_insight_cli.main import cli
 
 class TestCall(unittest.TestCase):
     def test_cli_works(self):
-        cli("./wf_test/main.nf", render_graphs=True)
+        #cli("./wf_test/main.nf", render_graphs=False)
         cli("./wf_test/main.nf", render_graphs=False)
 
     def test_cli_output_considered(self):