Describe the bug

After creating both a topic and a classroom and linking that topic to the classroom, deleting the topic causes console errors when visiting the classroom admin.

URL of the page where the issue is observed.

/classroom-admin

Steps To Reproduce

1. Go to the topics and skills dashboard page and create a topic.
2. Go to the classroom admin page and create a classroom and link that topic to it.
3. Delete the topic in the topics and skills dashboard page.
4. Go back to the classroom admin page and open the classroom that had the topic linked.

Expected Behavior

I expect no console errors to be present.

Screenshots/Videos

What device are you using?

Desktop

Operating System

Windows

What browsers are you seeing the problem on?

Chrome

Browser version

No response

Additional context

No response

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