[Accessibility] Workbench Page: Back button and Option dropdown not keyboard accessible

[nwanduka]

Describe the bug
The back button and options dropdown on the Workbench page are not keyboard focusable.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Workbench' in the nav bar
2. Press the tab key on your keyboard
3. See error

Expected behavior
Keyboard users should be able to navigate to and interact with the back button and options dropdown