[5.1] Media manager thumbnails better try/catch

[dgrammatiko]

Pull Request for Issue # .

Summary of Changes

The existing try/catch assumes that the class Image could be instantiated given a path. This might throw if avif or webp is not enabled in the GD (ie misconfigured PHP build).
The try/catch now will handle this in a more predictable way (won't break the media manager list view)

Testing Instructions

Code review, or just upload a new file (assume that the thumbs are enabled)

Actual result BEFORE applying this Pull Request

Expected result AFTER applying this Pull Request

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

@LadySolveig @bembelimen this PR is adjacent to #43295 (comment) so please consider merging it. Thanks

[LadySolveig]

I have tested this item ✅ successfully on 07c04b2

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[Quy]

I have tested this item ✅ successfully on 07c04b2

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/43468.}

[Quy]

RTC

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/43468.}

[bembelimen]

Thx