feat: add donut chart legend

Description This PR adds a feature from #876 for an optional legend to donut chart that's hidden by default, providing null to activeSector prop would show the legend with no default value and providing an index string from data would make the element active on page load

I added a new activeSector prop that receives undefined or null or string and it will make sector active upon page loading up and

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What kind of change does this PR introduce? (check at least one)

[ ] Bug fix (non-breaking change which fixes an issue)
[X] New Feature (non-breaking change which adds functionality)
[ ] New Feature (BREAKING CHANGE which adds functionality)
[ ] Refactor
[ ] Build-related changes
[ ] Other, please describe:

Does this PR introduce a breaking change? (check one)

[ ] Yes
[X] No

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The PR fulfils these requirements:

[ ] It's submitted to the main branch
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[ ] My change requires a change to the documentation. (Managed by Tremor Team)
[ ] I have added tests to cover my changes
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[ ] Add refs #XXX or fixes #XXX to the related issue section if your PR refers to or fixes an issue.
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tremorlabs / tremor

feat: add donut chart legend #982