Only pin Rails and json when RAILS_VERSION is set

Author: andrehjr

Gemfile

@@ -4,10 +4,12 @@ source "https://rubygems.org"
 
 gemspec
 
+rails_version = ENV.fetch("RAILS_VERSION", "8.1.0")
+
 gem "rubocop", require: false
 gem "codeclimate-test-reporter"
 gem "concurrent-ruby", "< 1.3.9"
 # json 3.0 dropped the quirks_mode option that ActiveSupport 7.2.3.x still passes
-gem "json", "< 3"
+gem "json", "< 3" if Gem::Version.new(rails_version) < Gem::Version.new("8.1")
 
-gem "rails", "~> #{ENV.fetch('RAILS_VERSION', '8.0')}"
+gem "rails", "~> #{rails_version}"