Remove reference to `shadow` in README.md since jarJar is being used
instead for NeoForge builds.
# Other notes
-This mod uses [shadow](https://github.com/johnrengelman/shadow) which is
-licenced under the [Apache License 2.0](https://github.com/johnrengelman/shadow/blob/master/LICENSE).
-
This mod also uses [JavaMP3](https://github.com/kevinstadler/JavaMP3)
which is licensed under the [MIT License](https://github.com/kevinstadler/JavaMP3/blob/master/LICENSE).