* expose checkout signup feature to release build (feature plugin):
- remove isExperimental from block/editor js (the block is already gated
to plugin only)
- gate entire service class to feature plugin && Woo >= 4.7
- this ensures our custom email and set password flow are only active
for supported woo version, if blocks plugin is active
- also refactored the gating logic so the woo version check is used to
gate all code
* eslint action told me to delete comment `.` ... ?
* remove experimental feature flag for checkout signup front-end:
- "Create Account?" checkbox in address/contact component
- logged-out prompt logic - handle case when signup is enabled and guest
checkout is not enabled, i.e. checkout requires automatic signup
* fix formatting issues
* add allowCreateAccount to proptypes for CheckoutForm and AddressStep
01132107a4