Fixed broken test case in GafferImageTest.FormatTest
Fixed broken test case in GafferImageTest.FormatTest

chippey/gaffer,andrewkaufman/gaffer,cedriclaunay/gaffer,andrewkaufman/gaffer,paulondc/gaffer,GafferHQ/gaffer,ImageEngine/gaffer,davidsminor/gaffer,chippey/gaffer,boberfly/gaffer,lucienfostier/gaffer,ivanimanishi/gaffer,ivanimanishi/gaffer,ImageEngine/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,goddardl/gaffer,chippey/gaffer,paulondc/gaffer,GafferHQ/gaffer,goddardl/gaffer,johnhaddon/gaffer,ivanimanishi/gaffer,hradec/gaffer,andrewkaufman/gaffer,johnhaddon/gaffer,boberfly/gaffer,andrewkaufman/gaffer,hradec/gaffer,cedriclaunay/gaffer,GafferHQ/gaffer,goddardl/gaffer,goddardl/gaffer,lucienfostier/gaffer,paulondc/gaffer,johnhaddon/gaffer,appleseedhq/gaffer,appleseedhq/gaffer,hradec/gaffer,ImageEngine/gaffer,cedriclaunay/gaffer,lucienfostier/gaffer,chippey/gaffer,ivanimanishi/gaffer,lucienfostier/gaffer,davidsminor/gaffer,GafferHQ/gaffer,paulondc/gaffer,davidsminor/gaffer,appleseedhq/gaffer,hradec/gaffer,hradec/gaffer,davidsminor/gaffer,appleseedhq/gaffer,andrewkaufman/gaffer,cedriclaunay/gaffer,johnhaddon/gaffer,boberfly/gaffer,GafferHQ/gaffer,boberfly/gaffer