[SECURITY] Fedora 31 Update: pngcheck-2.3.0-4.fc31

pngcheck verifies the integrity of PNG, JNG and MNG files (by checking the internal 32-bit CRCs [checksums] and decompressing the image data); it can optionally dump almost all of the chunk-level information in the image in human-readable form. For example, it can be used to print the basic statist ics about an image (dimensions, bit depth, etc.); to list the color and transparency info in its palette (assuming it has one); or to extract the embedded text annotations. This is a command-line program with batch capabilities. The current release supports all PNG, MNG and JNG chunks, including the new ly approved sTER stereo-layout chunk. It correctly reports errors in all but t wo of the images in Chris Nokleberg’s brokensuite-20061204.