Decision color-set should validate that there's at least one value

[vanessacor]

How to reproduce it

• create a color-set decision and set the params.value to an empty array:
  { "model": "color-set/explicit", "name": "Bar", "params": { "values": [] } }

What happens

Decision is not render and no feedback is given

What should happen

Validation should happen and an error should be display as a decision error

Fix

Related:

• Handle store errors #165
• Fallback to defaullts in case of input (generic) validation errors #169
• Make models resilient to input errors #170

In all set/scale of explicit models, declare that values needs to have at least 1 item

https://stackoverflow.com/questions/49910889/typescript-array-with-minimum-length