IONOS fix(Viewer): fix file filter for directories

[fracado]

No description provided.

[tanyaka]

Please consider to update the comment "don't include directories..." to something containing "... include only files with mimetypes"

No ";" at the end of line is needed too :-)

[matsaur]

Please consider to update the comment "don't include directories..." to something containing "... include only files with mimetypes"

No ";" at the end of line is needed too :-)

The idea behind the code is to not include directories, please use both wording in combination

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