Fix auto grading not working for multiple choice questions when multiple correct answers

[m1r0]

Depends on #6884

Proposed Changes

This fixes the multiple choice questions auto grading not working when there are multiple correct answers.

Testing Instructions

1. Create a quiz and add a multiple choice question that has multiple correct answers. Ensure that Auto Grade is disabled
2. As a student, take the quiz.
3. In Grading, find the quiz and click Grade quiz.
4. Click the Auto grade button.
5. The quiz should be graded correctly.
6. Make sure the grading works with a single correct answer as well.
7. Make sure the grading for all other question types is still working.

Pre-Merge Checklist

• PR title and description contain sufficient detail and accurately describe the changes
• Acceptance criteria is met
• Decisions are publicly documented
• Adheres to coding standards (PHP, JavaScript, CSS, HTML)
• All strings are translatable (without concatenation, handles plurals)
• Follows our naming conventions (P6rkRX-4oA-p2)
• Hooks (p6rkRX-1uS-p2) and functions are documented
• New UIs are responsive and use a mobile-first approach
• New UIs match the designs
• Different user privileges (admin, teacher, subscriber) are tested as appropriate
• Code is tested on the minimum supported PHP and WordPress versions
• User interface changes have been tested on the latest versions of Chrome, Firefox and Safari
• "Needs Documentation" label is added if this change requires updates to documentation
• Known issues are created as new GitHub issues

[github-actions]

WordPress Dependencies Report

The github-action-wordpress-dependencies-report action has detected some script changes between the commit 04c30bd and trunk. Please review and confirm the following are correct before merging.

Script Handle	Added Dependencies	Removed Dependencies	Total Size	Size Diff
js/grading-general.js			2.69 kB	+30 B ( +1.13% 🔼 )

This comment was automatically generated by the github-action-wordpress-dependencies-report action.

[codecov]

Codecov Report

Merging #6906 (04c30bd) into trunk (72678a9) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##              trunk    #6906   +/-   ##
=========================================
  Coverage     46.88%   46.88%           
  Complexity    10190    10190           
=========================================
  Files           554      554           
  Lines         36751    36751           
  Branches        381      381           
=========================================
  Hits          17230    17230           
  Misses        19215    19215           
  Partials        306      306           

see 1 file with indirect coverage changes

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[donnapep]

I actually can't get auto-grading to work. When I click Auto Grade for this quiz, nothing happens. 🤔

[m1r0]

Are you testing on an entry that was already graded/saved? If yes, could you try on a new grading entry? I've noticed that the auto-grade is not working for already graded/saved entries but that's another issue...

Here's how it looks on my end:

CqQ4GC.mp4

[merkushin]

Works great for multiple correct answers, thank you! 👍