Remove deprecation notice on nullable properties in method signatures

[LaurentBrieu]

Environment

• Checkout SDK version: 3.2.7
• Operating System and version: MacOS 14.2.1

Description

Update methods signatures to avoid deprecation notices when using PHP 8.4 :

Checkout\Payments\PaymentsClient::capturePayment(): Implicitly marking parameter $captureRequest as nullable is deprecated, the explicit nullable type must be used instead
Checkout\Payments\PaymentsClient::refundPayment(): Implicitly marking parameter $refundRequest as nullable is deprecated, the explicit nullable type must be used instead
Checkout\Payments\PaymentsClient::voidPayment(): Implicitly marking parameter $voidRequest as nullable is deprecated, the explicit nullable type must be used instead
Checkout\Payments\PaymentsClient::incrementPaymentAuthorization(): Implicitly marking parameter $authorizationRequest as nullable is deprecated, the explicit nullable type must be used instead

Proposed Solution

Generally speaking, across the whole project, it will be cool to set the expected types in method signatures, so that we don't have that kind of deprecations in the future.

Regarding the ones i've mentionned above, here's a quick fix.

public function capturePayment($paymentId, CaptureRequest $captureRequest = null, ?string $idempotencyKey = null)
public function refundPayment($paymentId, RefundRequest $refundRequest = null, ?string $idempotencyKey = null)
public function voidPayment($paymentId, VoidRequest $voidRequest = null, ?string $idempotencyKey = null)
public function incrementPaymentAuthorization($paymentId, AuthorizationRequest $authorizationRequest = null, ?string $idempotencyKey = null)

• I may be able to implement this feature

[LaurentBrieu]

Any news regarding this issue ? Would it be possible to do a commit on my own ?