1 extra question can be submitted

[adarsh-sgh]

Describe the bug
With default settings when all 10 questions are done and last question is auto submitted you can press Enter key to submit last answer once again and it will affect the user score.

To Reproduce
Steps to reproduce the behavior:

1. solve all question in a session
2. after last question is autosubmitted press enter
3. Question is submitted again

Expected behavior
Question can be submitted only once

[github-actions]

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