Change sass-lint for stylelint

[emteknetnz]

sass-lint is abandoned - its recommended replacement is stylelint

This was originally upgraded as part of the change to the frontend build stack, though this was later reverted as stylelint is currently non-functional due to the lack of stylelintrc.yml files

We need to change all the sass-lint.yml files in modules to stylelintrc.yml files instead i.e. https://dev.to/stories_of_ren/switching-from-sass-lint-to-stylelint-5f8c

This should probably only be done for CMS5

Related

• sass-lint was abandoned 5 years ago webpack-config#69

ACs

• Update silverstripe/webpack-config from sass-lint to stylelint
• yarn update all modules that use webpack-config
• Add stylelintrc.yml files to modules
  • If this requires a lot of configuration, that configuration is added to a separate NPM package which we can reference from all modules, similar to https://github.com/silverstripe/eslint-config/
• Remove sass-lint.yml files from modules
• Linting passes without errors or warnings on all core and supported modules

[GuySartorelli]

Closing as duplicate of silverstripe/webpack-config#69