pcx: Switch test images out

[lupine]

The PCX images included in #2364 have dubious licenses. The CGA ones may be LGPL or GPL (provenance breadcrumb: https://samples.ffmpeg.org/image-samples/pcx/cga/cga-pcx.txt ), while the marbles ones appear to be copyright O'Reilly, with no license grant (https://netghost.narod.ru/gff/sample/images/pcx/index.htm ).

It's worth noting that the tests/ directory is excluded from the crate build, but it's still worth swapping these out for an unambiguously OK image. To do that, I converted the tests/images/bmp/images/V5_24_Bit.bmp to a 24-bit PCX file:

$ file tests/images/pcx/images/24bit.pcx 
tests/images/pcx/images/24bit.pcx: PCX ver. 3.0 image data bounding box [0, 0] - [434, 352], 3 planes each of 8-bit colour, 72 x 72 dpi, RLE compressed

I then downsampled that to a 256-colour paletted image, to exercise both of the code paths we call in the pcx crate.

$ file tests/images/pcx/images/256-palette.pcx 
tests/images/pcx/images/256-palette.pcx: PCX ver. 3.0 image data bounding box [0, 0] - [434, 352], 8-bit colour, 72 x 72 dpi, RLE compressed

cc @HeroicKatora @fintelia

[kornelski]

@HeroicKatora The PCX supoprt has been merged recently. Maybe rebase+fixup and force-push the main branch to purge the old images from git history?

[fintelia]

Feel free to disable the branch protection, force-push a fixup, and then re-enable the protection

[kornelski]

I don't have permissions to access settings. I've created https://github.com/image-rs/image/tree/main-rebased branch that you can push

git push origin -f 9ee68e2afaff118987e953e470cf7221d5f04e71:main

[fintelia]

Done. Thanks everyone