Sketch block: Add default and custom color palettes

[oskosk]

Before	After

• Adds default and custom color palettes
• Fixes warning about deprecated isAlternate prop on Popover component
• Adds padding to color palette popover
• Fixes selected value prop name passed to ColorPalette

[oskosk]

It seems like these changes don't work with WordPress 6.1.1. Only with Gutenberg 15.2.3. I'm checking how to address this