[BUGFIX] Handle processed file paths properly

When implementing a custom ImageViewHelper to manipulate the image
with the GifBuilder, after processing instructions has been applied,
the processed image in the typo3temp/assets/images folder was a
1x1px sized image.
This happened because the ContentObjectRenderer::getImgResource()
returned null instead of an ImageResource, when the path of a processed
file was passed as $file argument.

It turned out, that the return of
ResourceFactory::retrieveFileOrFolderObject() also can be an instance of
ProcessedFile. So that the @return annotation had to be expanded by this
class.

The change in ContentObjectRenderer::getImgResource() now handles paths
of processed files properly.

Resolves: #103872
Releases: main
Change-Id: Ie67b77b680a339054bcf99d522234cb1d10e2ca6
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/84337


Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>