Refactor address_row fields
[core] Hides shipping address form if Use Billing Address checkbox is checked [admin]

[Fixes #2456]
Refactor spaces in syntax
[api] Return relative attachment url for product images
correctly show variant options

Fixes #2466
Reset preferences after spec to properly teardown test and avoid files being saved where they are not gitignored.

Fixes #2467
Use pluck instead of mapping attributes for performance.

Fixes #2468