Ensure tests are not swallowing errors

[aeweidne]

"Per hubot-ibmcloud-space-management and ibm-cloud-solutions/hubot-ibmcloud-space-management#17, the tests in this repo need to be investigated and probably updated if they are found to be swallowing errors or not surfacing them through the test runner correctly. The recommended practice is to use the portend library used in hubot-ibmcloud-space-management in order to test the emits generated by our scripts. This practice is outlined in the contributing.md of hubot-ibmcloud-space-management. When the tests are updated here, the contributing.md of this project must be updated as well."