Correct the return of type of function _columnBrake in module-theme block topMenu.php

[Krielkip]

Description (*)

Function _columnBrake return null when limit is smaller then $total.
But _getHtml needs the result to be array, which is being called in _getSubmenu.

Fixed Issues (if relevant)

1. Module-Theme: TopMenu invalid type of value returned #24251: Module-Theme: TopMenu invalid type of value returned

Manual testing scenarios (*)

1. Code review the functions: _columnBrake, _addSubMenu and _getHtml

Questions or comments

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 are green)

[m2-assistant]

Hi @Krielkip. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento give me test instance - deploy test instance based on PR changes
• @magento give me 2.3-develop instance - deploy vanilla Magento instance

For more details, please, review the Magento Contributor Guide documentation.

[magento-engcom-team]

Hi @sidolov, thank you for the review.
ENGCOM-5686 has been created to process this Pull Request
✳️ @sidolov, could you please add one of the following labels to the Pull Request?

Label	Description
Auto-Tests: Covered	All changes in Pull Request is covered by auto-tests
Auto-Tests: Not Covered	Changes in Pull Request requires coverage by auto-tests
Auto-Tests: Not Required	Changes in Pull Request does not require coverage by auto-tests

[m2-assistant]

Hi @Krielkip, thank you for your contribution!
Please, complete Contribution Survey, it will take less than a minute.
Your feedback will help us to improve contribution process.