Exception throw when calling Paddle\SDK\Entities\Event::from() with SubscriptionUpdated event

[tigerbook73]

Describe the bug

When try to build a SubscriptionUpdated Notification from Paddle\SDK\Entities\Event::from(data), exception thrown.

Reason:
In the subscription.updated event, the event.data.discount.started_at field may be null in a special scenario. This makes the invoking of Paddle\SDK\Entities\Event::from() failed.

Steps to reproduce

1. create a subscription
2. update the subscription with and discount start from next period
3. cancel the subscription immediately
4. an subscription.updated notification will be emitted. In this notfication, the subscription.discount.starts_at is null.
5. when try to build Paddle\SDK\Notifications\Events\SubscriptionUpdated from this event by calling Paddle\SDK\Notifications\Events::from($data), exception thrown at Paddle\SDK\Notifications\Entities\Subscription\SubscriptionDiscount::from()
   Line: 29 DateTime::from($data['starts_at'])

"message": "Paddle\SDK\Notifications\Entities\DateTime::from(): Argument #1 ($date) must be of type DateTimeInterface|string, null given,

Expected behavior

SubscriptionUpdated object can be successfully constructed from Event::from(...) call.

Code snippets

No response

PHP version

PHP 8.1

SDK version

paddle-php-sdk 1.20.1

API version

Paddle verson 1

Additional context

No response

[davidgrayston-paddle]

Hello @tigerbook73 👋 Thank you for raising this issue.

We'll make a fix for this in the next patch release, and will update this issue accordingly