[WIP][BD-13][BB-6732] refactor: Remove unused XModule classes

[0x29a]

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[openedx-webhooks]

Thanks for the pull request, @0x29a!

This is currently a draft pull request. When it is ready for our review and all tests are green, click "Ready for Review", or remove "WIP" from the title, as appropriate.

[Cup0fCoffee]

@0x29a Can you please close this PR in favor of #31173?

[openedx-webhooks]

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