Requests using png.quality sometimes fail

Exception and config linked below. Aside from default quality, we're using h, w, and mode=crop. Some images work perfectly, others don't. If we add scale=both, images that would otherwise fail don't.

[imageflowException.txt](https://github.com/imazen/imageflow-dotnet-server/files/14102117/imageflowException.txt)
[imageflowConfig.txt](https://github.com/imazen/imageflow-dotnet-server/files/14102146/imageflowConfig.txt)

Start by reviewing imageflowException.txt and imageflowConfig.txt, then reproduce requests using png.quality with h, w, and mode=crop. Compare failing cases with equivalent requests that add scale=both; done means the failure is explained and the affected behavior is covered by a reproducible test.

Written by the indexing model from the issue text.