Accessing "sprites[SPR2_STND]" on a skin_t outputs the "sprites" array of the skin_t instead

Test script: SkinSpritesArrayBugTest.wad

Special thanks to Monster Iestyn for confirming that this is an SRB2 bug and not a bug with my script.

Apparently, someone already made an issue for this two years ago: #558

As of 2.2.14, this bug still happens with skin_t.sprites, but now it also happens with skin_t.skinsprites and skin_t.supersprites:

Test script: SkinSpritesArrayBugTest2.lua