[4.4] Fix articles categories module bug

[joomdonation]

Pull Request for Issue #42924.

Summary of Changes

Currently, children categories are being displayed multiple times on articles categories module, see #42924 to understand more about the issue. This PR just fixes that wrong behavior.

Testing Instructions

Follow instructions at #42924 to create the module and confirm the issue

Actual result BEFORE applying this Pull Request

Children categories are being displayed multiple times, both at top level and children level

Expected result AFTER applying this Pull Request

Each category will only be displayed one time as expected.

Link to documentations

Please select:

• No documentation changes for docs.joomla.org needed
• No documentation changes for manual.joomla.org needed

[woluweb]

I have tested this item ✅ successfully on 9cbbe59

I have tested this successfully

• on J4
• on J5

Txs Tuan!

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[Quy]

I have tested this item ✅ successfully on 9cbbe59

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/42925.}

[Quy]

RTC

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[laoneo]

Thanks!