Reverts ColorPalette disableAlpha #18175

[mkaz]

Description

Reverts the change made in #18175 introducing the disableAlpha property to pass forward.

@youknowriad raised some good issues since the ColorPalette returns an hex code, that does not accept the alpha parameter it makes the additional feature unusable, or at least setting the channel does not get returned with the parameters.

The solution is likely to switch to returning rgba syntax if disableAlpha is false, reverting that change so we can address.

How has this been tested?

Previous state prior to #18175 being enabled.

[jorgefilipecosta]

Hi @mkaz, I checked the reason why this was being disabled:
onChangeComplete={ ( color ) => onChange( color.hex )

It seems like we could change that code and if an alpha component is set instead of passing a text color one may pass a color in the format "rgba( ... )".
I think the main question now is do we want to continue the update and support an alpha channel?

[mkaz]

@jorgefilipecosta heh, thanks - I rushed to put the revert together and I was going to look at the code after. Fixing up the code looks like it might be easier than the revert.

Any reason we wouldn't want to support it? The underlying React component supports it, so seems fair to give that flexibility to someone using this component.

[youknowriad]

rgba when this prop is enabled is just one of the different options, maybe we can revert in order to put some thoughts about the best way forward?

[youknowriad]

I'm going to land this to avoid including in the next Gutenberg release.

[jorgefilipecosta]

Any reason we wouldn't want to support it? The underlying React component supports it, so seems fair to give that flexibility to someone using this component.

I don't think we have a reason for not including it.