fix: correctly set and render prices for variants and options in product

[willopez]

Impact: minor
Type: bugfix

Issue

Not able to set prices on variants nor options

Solution

There was an underlying with the way prices were stored for variants and options. The issue has been resolved in the API and this PR makes adjustments necessary to use the new pricing field.

Breaking changes

None

Testing

1. Create a product with a least one variant, no options.
2. Verify the price and compare at price can be set on the variant and saves correctly
3. Add an option to the existing variant
4. Set price and compare at price and verify it saves correctly.