Fix ImageTest::testSaveError on unix
Fix ImageTest::testSaveError on unix

Bionus/imgbrd-grabber,YoukaiCat/imgbrd-grabber,Bionus/imgbrd-grabber,Bionus/imgbrd-grabber,Bionus/imgbrd-grabber,Bionus/imgbrd-grabber,YoukaiCat/imgbrd-grabber,Bionus/imgbrd-grabber