add more model tests

spec/rails_helper.rb

@@ -8,6 +8,8 @@ abort("The Rails environment is running in production mode!") if Rails.env.produ
 require 'rspec/rails'
 # Add additional requires below this line. Rails is not loaded until this point!
 
+require "action_cable/testing/rspec"
+
 # Requires supporting ruby files with custom matchers and macros, etc, in
 # spec/support/ and its subdirectories. Files matching `spec/**/*_spec.rb` are
 # run as spec files by default. This means that files in spec/support that end