[BUG] Content accessible without login when JavaScript is disabled on lesson page

Describe the bug
When a user tries to access a lesson page that is supposed to be restricted to authenticated users (via GitHub or Google login), the content is accessible if JavaScript is disabled in the browser.

To Reproduce
Steps to reproduce the behavior:

1. Open the platform in a browser (e.g., Chrome, Firefox, etc.).
2. Disable JavaScript in the browser settings.
3. Visit a lesson page that should be restricted to logged-in users.
4. Observe that the content is still visible, even though the user is not logged in.

Expected behavior

• The lesson page content should only be visible to users who are authenticated via GitHub or Google login.
• If JavaScript is disabled, the content should be hidden or the user should be redirected to the login page.

Desktop

• OS: Arch Linux (btw)
• Browser: Chromium/Firefox