An incident that is closed with a slash command can be closed again from the RHS details view without any error.
1. Create an incident.
2. Open the incident RHS and find the incident started in step 1.
3. Click on the incident to go to the details view.
4. Click on the incident channel to load the incident channel in the center.
5. With RHS still in incident details view, Issue the `/incident end` command.
6. The "incident has been closed" message appears in the center channel.
Expected: Step 6 - The RHS view changes to indicate that the incident has been ended.
Observed: The `End Incident` button remains active and when clicked on it, a second "incident has been closed" message appears in the center channel and the details view changes to list view and shows active incidents.