[Apple] Check for cancellation_date_ms first

If cancellation date is available it means that Apple Customer Support refunded subscription payment.

From Apple:
To check whether a purchase has been canceled by Apple Customer Support, look for the
Cancellation Date field in the receipt. If the field contains a date, regardless of the
subscription’s expiration date, the purchase has been canceled. With respect to providing
content or service, treat a canceled transaction the same as if no purchase had ever been made.

Referencing the following documentation:

https://developer.apple.com/documentation/appstorereceipts/status

We can see that 21009 and 21010 are available codes we should handle.

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verifyPayment and cancelSubscription now return promises if no callback is passed

…nto google-defer