feat(ai-spinner-icon): make spinner colors configurable

[AdrianArenal]

currentColor usage, to avoid things like:

.x-ragno [data-test='no-results-icon'] svg polygon,
.x-ragno [data-test='no-results-icon'] svg ellipse {
  fill: var(--xds-color-neutral-0) !important;
  stroke: var(--xds-color-neutral-0) !important;
}

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