Namespace radio buttons for CMY/RGB colour mixers

[michaelmcleodnz]

Proposed changes

Minor fix: The CMY and RGB colour mixers are meant to appear on the same page (5.5), but the radio buttons for both interactives have the same names and IDs, contrary to most other elements in those interactives. This pull request gives the radio buttons different names and IDs, consistent with other elements, so that clicking a radio button in one interactive doesn't produce unexpected behaviours in the other.

Checklist

• I have read the contribution guidelines.
• N/A I have linked any relevant existing issues/suggestions in the description above (include #??? in your description to reference an issue, where ??? is the issue number).
• The pull request is requesting a merge into the develop branch.
• N/A I have added necessary documentation (if appropriate).
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[jimbonothing64]

Great spot! These changes look good, merge it in when you're ready. Thanks!

[michaelmcleodnz]

Hi James, I can't do these merges myself as I'm just a random member of the public (a teacher in Auckland) and don't have write-access to the repository. This applies to this pull request and to #2483.

[jimbonothing64]

Apologies, that's correct. I'll merge them in now. Thanks again for contributing Michael!