Add HEADLESS env for specs

Author: route

spec/spec_helper.rb

@@ -21,6 +21,7 @@
   options = {}
   options.merge!(inspector: true) if ENV["INSPECTOR"]
   options.merge!(logger: StringIO.new) if ENV["CI"]
+  options.merge!(headless: false) if ENV["HEADLESS"] == "false"
   Capybara::Cuprite::Driver.new(app, options)
 end