🐛[Sass] Fix recolor-icon mixin

[beefchimi]

This PR safely moves color: $secondary-color into the svg block alongside fill: $primary-color.

Previously, the mixin was expected to be used like so:

.Component {
  color: blue;
  // more styles for the component
  @include recolor-icon(red, green);
}

Within the recolor-icon mixin, fill was scoped to to the svg selector... but color was outside of it. This meant that in the above example, my color: blue will get overridden with green, when really my intention is to have .Component use blue text, while making the primary color of the icon red and the secondary color of the icon green.

[github-actions]

💦 Potential splash zone of changes introduced to src/**/*.tsx in this pull request:

No significant changes to src/**/*.tsx were detected.

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[kaelig]