Created Unassigned: ImageMagick.MagickCorruptImageErrorException [1372]

This image seems to be valid in other apps but Magick (Q8-AnyCPU 7.0.0.0022) is puking on it with the following stack trace:

```
at ImageMagick.Wrapper.MagickImage.Read(Stream stream, MagickReadSettings readSettings)
at ImageMagick.MagickImage.Read(Stream stream, MagickReadSettings readSettings)
at ImageMagick.MagickImage.Read(Stream stream)

```

The message is "Invalid colormap index `' @ error/image.c/SyncImage/3563"