Rename colliding type parameters when translating sigs to RBS

[Hashim1999164]

Summary

• RBS type variables shadow constants and class type members that share the same name, so a translated sig can fail to parse or drop a type error
• When a method type parameter collides with a constant path or class type member in the same signature, rename it before printing the RBS comment

Closes #1012

Test plan

• bundle exec rake test