run composer install in sage theme folder

#
# Run 'composer install' in the theme directory
namespace :deploy do
  desc 'Composer install'
  task :composer_install do
    on roles(:app) do
      set :theme_path, fetch(:release_path).join('web/app/themes/',fetch(:theme_dir))
      within fetch(:theme_path) do
        execute :composer, :install
      end
    end
  end
end
## Runs the above task after publishing
after 'deploy:publishing', 'deploy:composer_install'
###