message: Fix gracefully handle null color in Graphics
diff: @@ -631,7 +631,7 @@ export class Graphics extends Container
  */
  private normalizeColor(options: Pick<IFillStyleOptions, 'color' | 'alpha'>): void
  {
  - const temp = Color.shared.setValue(options.color);
  + const temp = Color.shared.setValue(options.color ?? 0);
  options.color = temp.toNumber();
  options.alpha ??= temp.alpha;
  