Framework's matchesGoldenFile should assert that file name has right structure #98943
Description
#98772 broke the tree because the file name provided to matchesGoldenFile was missing .png. We should assert that file names have the right structure - maybe even that they are unique at least for the given file?
incorrect:
matchesGoldenFile('slider_start_text_scale_1_width_0'),correct:
matchesGoldenFile('slider_start_text_scale_1_width_0.png'),