[6.1] Add intro image to RSS feed item description in com_tags

[keep]

Pull Request for Issue #44693

Summary of Changes

When generating a feed from com_tags, this change prepends the intro image (if available) to the feed item's description using an tag.

Testing Instructions

Create a tagged article that has an intro image. Open the tag feed Check that the feed item description starts with the intro image as an HTML element.

Actual result BEFORE applying this Pull Request

The feed item description contains only the article body text.

Expected result AFTER applying this Pull Request

If the article has an intro image, it is included before the description text in the feed.

Link to documentations

Please select:

• [ ] Documentation link for docs.joomla.org:

• [x] No documentation changes for docs.joomla.org needed

• [ ] Pull Request link for manual.joomla.org:

• [x] No documentation changes for manual.joomla.org needed

[MacJoom]

I have tested this item :red_circle: unsuccessfully on c3906ee66e11f087e9e954fcf772dc40ebdd6aae

I'm getting an error after applying the Patch: Class "Joomla\Component\Tags\Site\View\Tag\HTMLHelper" not found

is an

use Joomla\CMS\HTML\HTMLHelper;

missing?

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/45455.}

[drmenzelit]

I have tested this item :red_circle: unsuccessfully on c3906ee66e11f087e9e954fcf772dc40ebdd6aae

Getting an error, when trying to open the feed 0 Class "Joomla\Component\Tags\Site\View\Tag\HTMLHelper" not found

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/45455.}

[HLeithner]

This pull request has been automatically rebased to 5.4-dev.

[HLeithner]

This pull request has been automatically rebased to 6.1-dev.