Fixes decline invitation

[akolson]

Summary

Description of the change(s) you made

This pr fixes the issue with a declined invitation popping up again. This fix updates the accept endpoint to allow for declining of invitations.

Manual verification steps performed

1. Go to https://unstable.studio.learningequality.org/en/accounts/#/ and sign in as user A
2. Open a channel and select the 'Share channel' option
3. Share the channel with user B by either selecting the 'Can view' or 'Can edit' option
4. Sign in as user B and decline the invitation
5. Refresh the 'My channels' page and observe that the invitation message has reappeared

Screenshots (if applicable)

Screen.Recording.2024-09-23.at.21.44.49.mov

Does this introduce any tech-debt items?

• No

Reviewer guidance

How can a reviewer test these changes?

• See Manual verification steps performed

Are there any risky areas that deserve extra testing?

• Because the fix updates the accept invitation endpoint, it would be great to do some extra testing to verify that the accept invitation is working correctly.

References

Fixes #4743

Fixes #4744

Comments

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Contributor's Checklist

PR process:

• If this is an important user-facing change, PR or related issue the CHANGELOG label been added to this PR. Note: items with this label will be added to the CHANGELOG at a later time
• If this includes an internal dependency change, a link to the diff is provided
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• If any Python requirements have changed, the updated requirements.txt files also included in this PR
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Studio-specifc:

• All user-facing strings are translated properly
• The notranslate class been added to elements that shouldn't be translated by Google Chrome's automatic translation feature (e.g. icons, user-generated text)
• All UI components are LTR and RTL compliant
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Testing:

• Code is clean and well-commented
• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Any new interactions have been added to the QA Sheet
• Critical and brittle code paths are covered by unit tests

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Reviewer's Checklist

This section is for reviewers to fill out.

• 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

[LianaHarris360]

I can confirm that declining and accepting the invitation works as expected and does not reappear when the page is loaded. There was just one thing I had a comment about that could possibly cause confusion.

[LianaHarris360]

Accepting and declining an invitation to view and edit a channel works as expected and the code changes make sense to me, thank you!