Fix Cron Error When Product Has Been Deleted

[sprankhub]

• The code is working on a plain Magento 2 installation.
• The code follows the PSR-2 code style.
• When an exception or error is logged the message is accompanied with some context, eg: Error when trying to get the payment status:
• Contains tests for the changed/added code (great if so but not required).
• I have added a scenario to test my changes.

This PR touches code in the following areas (Check what is applicable):

Frontend

• Shopping cart
• Checkout
• Totals
• Payment methods

Backend

• Configuration
• Order grid
• Order view
• Invoice view
• Credit memo view
• Shipment view
• Email sending

Order Processing (Mollie communication)

• Creating the order
• Invoicing the order
• Shipping the order
• Refunding (credit memo) the order

Other
Second Chance Email

Please describe the bug/feature/etc this PR contains:

The following cronjob failed:

Job	mollie_send_pending_payment_reminders
Messages	Error when running a cron job: Call to a member function isSaleable() on null
Executed at	2025-05-02 09:00:09

Scenario to test this code:

1. Configure second chance email.
2. Cancel order payment.
3. Delete ordered product.
4. Wait for second chance email cronjob.
5. Observe above error.

[Frank-Magmodules]

Thanks as always for your PR and contribution, @sprankhub!
We’ll review it shortly and include it in the next release if approved.