`ColorPickerWidget` throws an NPE when allowAlpha is false.

[Emirlol]

The exception is thrown upon clicking on the color picker button to open the picker. In ColorPickerWidget#render:

YetAnotherConfigLib/src/main/java/dev/isxander/yacl3/gui/controllers/ColorPickerWidget.java

Lines 151 to 155 in 5bf53ce

	//? if >=1.21.9 {
	if (isHoveringHueSlider(mouseX, mouseY)) {
	graphics.requestCursor(com.mojang.blaze3d.platform.cursor.CursorTypes.RESIZE_EW);
	} else if (isHoveringAlphaSlider(mouseX, mouseY)) {
	graphics.requestCursor(com.mojang.blaze3d.platform.cursor.CursorTypes.RESIZE_EW);

The picker opens towards the bottom so the hue slider check is false,

so the else if branch for the alpha slider is entered next, which checks for the dimensions of the alphaGradientDim field:

YetAnotherConfigLib/src/main/java/dev/isxander/yacl3/gui/controllers/ColorPickerWidget.java

Lines 200 to 203 in 5bf53ce

	private boolean isHoveringAlphaSlider(double mouseX, double mouseY) {
	return mouseY >= alphaGradientDim.y() && mouseY <= alphaGradientDim.yLimit()
	&& mouseX >= alphaGradientDim.x() && mouseX <= alphaGradientDim.xLimit();
	}

But this field is only initialized from ColorPickerWidget#setDimension, and is otherwise null:

YetAnotherConfigLib/src/main/java/dev/isxander/yacl3/gui/controllers/ColorPickerWidget.java

Lines 305 to 308 in 5bf53ce

	hueGradientDim = Dimension.ofInt(colorPickerDim.x(), colorPickerDim.yLimit() - sliderHeight - alphaSliderHeight, colorPickerDim.width(), sliderHeight);
	if (controller.allowAlpha()) {
	alphaGradientDim = Dimension.ofInt(hueGradientDim.x(), hueGradientDim.y() + alphaSliderHeight, hueGradientDim.width(), sliderHeight);
	}

Hence, a NPE is thrown.