Workflow while navigating through Cohorts.

Steps to reproduce issue:

1. On dashboard, click on Cohorts, sync any cohort if none are synced already.
2. Click on any synced cohort, this would lead to the list of clients corresponding to that cohort.
3. Click the back button (either the one on the top left of the screen/ the back button of the device). Under normal circumstances, the user would want to be directed back to the list of synced cohorts i.e. the previous activity on the stack, but instead is redirected to the dashboard, which is undesirable from a user's perspective.