* Refactored the charge succeeded handler a bit
* If refund charge is received, and we don't have a parent transaction stored already, attempt to create one
* Converted else if structure to switch-case
* Moved logic for invoice.upcoming to a private method
* Moved logic for charge.succeeded to a private method
* Moved logic for charge.refunded to a private method
* Moved logic for invoice.payment_succeeded to a private method
* Updated invoice.payment_failed to match the rest
* Updated invoice.created to match the rest with some light refactors
* Added method comment to HandlePaymentMethodAttachedAsync
* Moved logic for customer.updated to a private method
* Updated logger in default case
* Separated customer.subscription.deleted and customer.subscription.updated to be in their own blocks
* Moved logic for customer.subscription.deleted to a private method
* Moved logic for customer.subscription.updated to a private method
* Merged customer sub updated or deleted to switch
* No longer checking if the user has premium before disabling it since the service already checks
* Moved webhook secret parsing logic to private method
* Moved casting of event to specific object down to handler
* Reduced nesting throughout
* When removing secrets manager, now deleting 100% off password manager discount for SM trials
* Added method comment and reduced nesting in RemovePasswordManagerCouponIfRemovingSecretsManagerTrialAsync
* Added feature flag constant
* Wrapped Automatic Tax logic behind feature flag
* Only getting customer if feature is anabled.
* Enabled feature flag in unit tests
* Made IPaymentService scoped
* Added missing StripeFacade calls
* Removed TaxRate logic when creating or updating a Stripe subscription and replaced it with AutomaticTax enabled flag
* Updated Stripe webhook to update subscription to automatically calculate tax
* Removed TaxRate unit tests since Stripe now handles tax
* Removed test proration logic
* Including taxInfo when updating payment method
* Adding the address to the upgrade free org flow if it doesn't exist
* Fixed failing tests and added a new test to validate that the customer is updated
