Fix bug with quiz next button skipping questions

[lesterong]

What is the purpose of this pull request?

• Documentation update
• Bug fix
• Feature addition or enhancement
• Code maintenance
• DevOps
• Improve developer experience
• Others, please explain:

Overview of changes:

Only allow the click event on the Next button in Quiz to be triggered once. Resolves #2188.

Anything you'd like to highlight/discuss:

NIL

Testing instructions:

NIL

Proposed commit message: (wrap lines at 72 characters)

Fix Quiz next button skipping questions

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Checklist: ☑️

• Updated the documentation for feature additions and enhancements
• Added tests for bug fixes or features
• Linked all related issues
• No unrelated changes

[yucheng11122017]

Hi @lesterong thanks very much for the work on this PR!
Gentle reminder not to delete the PR template when creating a PR :) You can just fill in nil for things if there's nothing to add and so on.
Also, could you try to add unit tests for this PR? Thanks!

[lesterong]

Hi @lesterong thanks very much for the work on this PR! Gentle reminder not to delete the PR template when creating a PR :) You can just fill in nil for things if there's nothing to add and so on. Also, could you try to add unit tests for this PR? Thanks!

@yucheng11122017, noted on that! I have edited my comment with the full template. Also, may I clarify what unit tests to add? It seems like the tests for the Quiz component were skipped in an earlier pull request #2244.

[itsyme]

Hi @lesterong thanks very much for the work on this PR! Gentle reminder not to delete the PR template when creating a PR :) You can just fill in nil for things if there's nothing to add and so on. Also, could you try to add unit tests for this PR? Thanks!

@yucheng11122017, noted on that! I have edited my comment with the full template. Also, may I clarify what unit tests to add? It seems like the tests for the Quiz component were skipped in an earlier pull request #2244.

hi @lesterong! the tests were disabled due to some unexpected behaviour with setTimeout being used in the tests causing CI to fail sometimes. perhaps you could test the fix locally but skip it when you commit so that we can unskip them when we solve #2238

[tlylt]

Checked on https://deploy-preview-2312--markbind-master.netlify.app/userguide/components/others#quizzes and the behavior seems to be corrected 👍

[yucheng11122017]

LGTM! Thanks @lesterong

[itsyme]

LGTM! I've checked out the tests as well and it seems to work as intended. Thanks @lesterong!

[itsyme]

@all-contributors please add lesterong for code

[allcontributors]

@itsyme

I've put up a pull request to add @lesterong! 🎉