[Backport] fix: Prevent error page recursion (#35209)

[cmltaWt0]

This is a backport of #35209

Fix details

We sometimes see rendering errors in the error page itself, which then cause another attempt at rendering the error page. I'm not sure exactly how the loop is occurring, but it looks something like this:

1. An error is raised in a view or middleware and is not caught by application code
2. Django catches the error and calls the registered uncaught error handler
3. Our handler tries to render an error page
4. The rendering code raises an error
5. GOTO 2 (until some sort of server limit is reached)

By catching all errors raised during error-page render and substituting in a hardcoded string, we can reduce server resources, avoid logging massive sequences of recursive stack traces, and still give the user some indication that yes, there was a problem.

This should help address #35151

At least one of these rendering errors is known to be due to a translation error. There's a separate issue for restoring translation quality so that we avoid those issues in the future (openedx/openedx-translations#549) but in general we should catch all rendering errors, including unknown ones.

Testing:

• In lms/envs/devstack.py change DEBUG to False to ensure that the usual error page is displayed (rather than the debug error page).
• Add line 1/0 to the top of the student_dashboard function in common/djangoapps/student/views/dashboard.py to make that view error.
• In lms/templates/static_templates/server-error.html replace static.get_platform_name() with None * 7 to make the error template itself produce an error.
• Visit http://localhost:18000/dashboard.

Without the fix, the response takes 10 seconds and produces a 6 MB, 85k line set of stack traces and the page displays "A server error occurred. Please contact the administrator."

With the fix, the response takes less than a second and produces three stack traces (one of which contains the error page's rendering error).

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[cmltaWt0]

Tested locally for dev and local tutor options using the following testing steps:

- In lms/envs/devstack.py change DEBUG to False to ensure that the usual error page is displayed (rather than the debug error page).
- Add line 1/0 to the top of the student_dashboard function in common/djangoapps/student/views/dashboard.py to make that view error.
- In lms/templates/static_templates/server-error.html replace static.get_platform_name() with None * 7 to make the error template itself produce an error.
- Visit http://localhost:18000/dashboard.

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@cmltaWt0 🎉 Your pull request was merged! Please take a moment to answer a two question survey so we can improve your experience in the future.

[OmarIthawi]

@cmltaWt0 thank you! I think this error has been going on for at least 5 years without an easy way to reproduce or fix. Thanks for fixing it!