fix: svg radialGradient fr attribute missing in types

[hrueger]

This fixes missing type for the fr attribute for radialGradients in svg tags.
Before, the following code threw a warning:

...
<radialGradient
  cx="0"
  cy="0"
  r={outerRadius}
  fr={innerRadius}
/>
...

/home/me/source/some-project/src/lib/components/Chart.svelte:208:5
Error: Object literal may only specify known properties, and '"fr"' does not exist in type 'HTMLProps<"radialGradient", SVGAttributes<any>>'. (ts)
                                r={outerRadius}
                                fr={innerRadius}
                                fx="0"

I'm not sure if this needs a test, but I don't think so.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 2b10f9d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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svelte	Patch

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[Rich-Harris]

thank you!