Check the original issue and create a test for it. Some test could be just changed to test this.

• Create an OpenShift Streams instance
• When instance is created, navigate into the instance with the UI
• Create a new topic
• In the "Create Topic" wizard, set the "Message Retention -> Retention Time" to "A day" or "Custom Duration -> {x}days".
• Create the topic
• Observe that the retention time of the topic is set to 7 days