merge method
Implementation
ZeroSliderStyle merge(ZeroSliderStyle? other) {
if (other == null) return this;
return copyWith(
activeColor: other.activeColor,
inactiveColor: other.inactiveColor,
tooltipVariant: other.tooltipVariant,
tickColor: other.tickColor,
thumbColor: other.thumbColor,
tickBehavior: other.tickBehavior,
tooltipColor: other.tooltipColor,
);
}