Remove lint roller

Author: mjankowski

docs/RUBY_VERSIONS.md

@@ -38,7 +38,6 @@ what was an already-EOL but still-supported older ruby version.
 
 We will align versions/dependencies amongst the Standard gems:
 
-- [lint_roller](https://github.com/standardrb/lint_roller)
 - [standard-custom](https://github.com/standardrb/standard-custom)
 - [standard-performance](https://github.com/standardrb/standard-performance)
 - [standard-rails](https://github.com/standardrb/standard-rails)