[trivial] remove unused import

Author: enebo

src/main/java/org/jruby/prism/parser/LoaderPrism.java

@@ -2,7 +2,6 @@
 
 import org.jcodings.Encoding;
 import org.jruby.Ruby;
-import org.jruby.util.ByteList;
 import org.ruby_lang.prism.Loader;
 import org.ruby_lang.prism.ParseResult;