Fixes issue where activeTabId is not set when viewing quiz reports for a group

[nathanaelg16]

Summary

This change appropriately sets the activeTabId to QuizzesTabs.REPORT so that the UI is rendered properly

Before

After

• No console errors produced

References

• #12132

Reviewer guidance

To test these changes:

1. Create a Quiz
2. Create a Group
3. Go to Coach > Reports > Groups > [group] > Reports > Quizzes assigned > [quiz] and try to select the "Report" tab
4. Observe the changes fix the UI bug described in the issue, and console errors are cleared

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Testing checklist

• [X] Contributor has fully tested the PR manually
• [X] If there are any front-end changes, before/after screenshots are included
• [ ] Critical user journeys are covered by Gherkin stories
• [ ] Critical and brittle code paths are covered by unit tests

PR process

• [ ] PR has the correct target branch and milestone
• [ ] PR has 'needs review' or 'work-in-progress' label
• [ ] If PR is ready for review, a reviewer has been added. (Don't use 'Assignees')
• [ ] If this is an important user-facing change, PR or related issue has a 'changelog' label
• [ ] If this includes an internal dependency change, a link to the diff is provided

Reviewer checklist

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md