Ensure push notifications re-register after store switch#16397

RafaelKayumov wants to merge 2 commits intotrunkwoocommerce/woocommerce-ios:trunkfrom

re-register-for-push-notifications-on-site-switchwoocommerce/woocommerce-ios:re-register-for-push-notifications-on-site-switchCopy head branch name to clipboard