[Forwardport] Cast products getStoreId() to int

[sreichel]

Description

Cast getStoreId() for products to int (like for categories).

Forwardport: #18086

Fixed Issues (if relevant)

1. Inconsistent return type for getStoreId() #18079:

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @sreichel. Thank you for your contribution
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[magento-engcom-team]

Hi @sidolov, thank you for the review.
ENGCOM-3061 has been created to process this Pull Request

[sreichel]

@sidolov whats wrong with this test? I dont see any problems at mentioned lines.

[magento-engcom-team]

Hi @sreichel. Thank you for your contribution.
We will aim to release these changes as part of 2.3.1.
Please check the release notes for final confirmation.