Ruby

Implement RBS prepend support with comprehensive tests #1154

Job	Run time
ruby-versions / Generate Ruby versions	3s
build (3.3)	49s
build (truffleruby-head)	30s
build (truffleruby)	36s
build (3.2)	42s
build (head)	44s
build (3.4)	47s
	4m 11s

Provide feedback