[1.12.2] Bundles and relies on outdated Kotlin

[LlamaLad7]

This mod relies on and bundles Kotlin 1.3.0, and makes use of experimental features at the time of development (unsigned types), and so when other mods bundle Kotlin 1.5.30, this mod breaks due to the unsigned types methods having changed. It would be great if you could compile against and bundle a more recent version.