[4.4] Atom Feed: Prevent notice from empty description

[Hackwar]

Pull Request for Issue #41824.

Summary of Changes

In PHP 8.2, the changed line creates a notice when calling a category blog view with ?format=feed&type=atom attached to the URL. This fixes that.

Testing Instructions

1. Open a category blog page on a site on PHP 8.2 and attach ?format=feed&type=atom to the URL.
2. Look at the output.

Actual result BEFORE applying this Pull Request

A notice is shown:
Deprecated: htmlspecialchars(): Passing null to parameter #1 ($string) of type string is deprecated in /home/www/libraries/src/Document/Renderer/Feed/AtomRenderer.php on line 89

Expected result AFTER applying this Pull Request

The notice is not there.

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed

[MacJoom]

I have tested this item ✅ successfully on 5c66558

On Jooma 4.4-dev PHP 8.2

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[viocassel]

I have tested this item ✅ successfully on 5c66558

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[richard67]

RTC

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[laoneo]

Thanks!