Enhance assets:clobber with css:clobber

[Intrepidd]

rails/jsbundling-rails#52 (comment)

[johnston]

Hi - I think this breaks when using https://github.com/rails/propshaft as it doesn't have an assets:clobber task: https://github.com/rails/propshaft/blob/a68fd6dab490f489c0fef49912a5aba03800b3ac/lib/propshaft/railtie.rb#L47-L64

❯ bundle exec rails css:install:postcss
rails aborted!
Don't know how to build task 'assets:clobber' (See the list of available tasks with `rails --tasks`)
Did you mean?  assets:clean
/Users/stuart/webapps/rails-new/ListBox/Rakefile:6:in `<main>'
bin/rails:4:in `<main>'
(See full trace by running task with --trace)

[Intrepidd]

Good point, does it make sense to have an assets:clobber task for propshaft ? As it generates assets into public/assets I guess it could

[dhh]

We should add assets:clobber to Propshaft. Please do PR that