Logged out when opening non-public VOD

[PRehker]

Describe the bug
When clicking on a link of a VOD on the homepage, I get logged out.

To Reproduce
Steps to reproduce the behavior:

1. Go to live.rbg.tum.de
2. log in to see a non-public course
3. try to open an old VOD
4. See error 403 and login button at the top of the page.

Expected behavior
Instead of having to log back in, display the stream and stay logged in.

Screenshots
https://github.com/TUM-Dev/gocast/assets/105861512/25ea76a6-ec04-4c1e-bd5c-bed5469d1bce

Desktop (please complete the following information):

• OS: MacOS
• Browser Chromium
• Version 122.0.6261.129

Smartphone (please complete the following information):

• Device: MacBook Air M1
• OS: macOS Sonoma 14.3.1
• Browser: Arc
• Version Chromium 122.0.6261.129

[YiranDuan721]

Thanks for the issue. I tried using a non-admin account, reproduced the problem, but my login status is not changed if I go back to the last page, or visit any valid TUM-Live page. I think the more important problem here is that the private VoDs are still publicly listed (#1266).

Back to the issue itself, comments / ideas wanted here: Is it a problem to have no user information on the 403 page?