Add stylelint to clean code linters list

Author: ntwb

collections/clean-code-linters/index.md

@@ -38,6 +38,7 @@ items:
  - golangci/golangci-lint
  - nicklockwood/SwiftFormat
  - super-linter/super-linter
+ - stylelint/stylelint
 display_name: Clean code linters
 created_by: holman
 ---