Gemfile in red_amber-0.2.3 vs Gemfile in red_amber-0.3.0

@@ -22,6 +22,7 @@
 
   gem 'benchmark_driver'
   gem 'red-arrow-numo-narray'
   gem 'red-datasets-arrow'
   gem 'simplecov'
+  gem 'simplecov-json'
 end