Items in notification inbox cannot be navigated by keyboard

Issue Summary

Disabled users who cannot use a mouse may rely on using the keyboard for navigating UI elements. When opening the inbox for notifications in the Bitbucket Server UI it's not possible to navigate through the items (i.e. notifications) using the arrow keys on the keyboard.

Steps to Reproduce

1. Open the notifications inbox if there are pending notifications
2. Use the arrow keys

Expected Results

The selection will cycle through the notifications

Actual Results

Nothing happens or the entire view of the window scrolls up and down

Workaround

You can use the tab key to navigate between items in the inbox.