[sku-selector] Decide whether SKU fields with a single value are displayed or not

[ivanlopezluna]

Is your feature request related to a problem? Please describe.
When the SKU fields in a product only have one possible value, it doesn't make sense to display the field in the SKU selector because the user will have no options to choose from and in some scenarios this is annoying for the user because they see multiple SKU fields with unique values.

Describe the solution you'd like
Having some prop that allows to decide whether or not the SKU selector should show the fields that only have a single value, so it will be possible to make a different decision in each VTEX store.

Describe alternatives you've considered
Add a CSS Handle that allows identifying the number of values that each SKU field has according to the selected product so that it is possible to customize them through CSS.

Additional context
Consider that the SKU fields with a single value are automatically selected and for this reason in some examples like the one we share it is not useful to show all the SKU fields that the product has.