bug: Download btn is working for non-authenticated users as well

[hxdy-1]

Describe the bug We should render the download button only if the user is logged in

To Reproduce Steps to reproduce the behavior:

1. Just go to any track
2. See the bug on the appbar

Expected behavior Only logged-in/authenticated users should be able to download the slides

Screenshots or GIFs User is not logged in but can still download the slides:

Info (please complete the following information):

• Browser [Chrome]
• Version [Latest]