Update Rails, Webpack, webpacker and misc dependencies (shakacode#490)

* Update Rails
* Fix selenium-webdriver version, Update test
* Update Webpack config
* Update .scss into .module.scss
* Reintroduce ActionCable config
* Update react-intl and update .scss into .module.scss
* Update Procfile
* Fix ReactOnRails JSX return warning
* Fix PropType warnings fo react-intl
* Update postcss
* Fix ActionCable self is undefined issue
* Update rails defaults

Author: gscarv13

.gitignore

@@ -27,8 +27,8 @@ vendor/ruby
 .ruby-gemset
 
 # Generated js bundles
-/public/webpack/
-/public/webpack-test/
+/public/packs
+/public/packs-test
 
 # Rubymine/IntelliJ
 .idea
@@ -38,3 +38,7 @@ spec/examples.txt
 # Ignore i18n-js
 client/app/libs/i18n/translations.js
 client/app/libs/i18n/default.js
+
+/yarn-error.log
+yarn-debug.log*
+.yarn-integrity

Gemfile

@@ -1,17 +1,16 @@
 # frozen_string_literal: true
 
 source "https://rubygems.org"
-ruby "2.7.1"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
-gem "react_on_rails", "12.0.1"
-gem "webpacker"
+ruby "2.7.3"
+
+gem "react_on_rails", "12.5.2"
+gem "webpacker", "6.0.0.rc.6"
 
 # Bundle edge Rails instead: gem "rails", github: "rails/rails"
 gem "listen"
-gem "rails", "~> 5"
-
-# Note: We're using sqllite3 for development and testing
-# gem "sqlite3", group: [:development, :test]
+gem "rails", "~> 6.1.4"
 
 gem "pg"
 
@@ -44,7 +43,7 @@ gem "rails-html-sanitizer"
 
 # See https://github.com/sstephenson/execjs#readme for more supported runtimes
 # mini_racer is probably faster than therubyracer
-gem "mini_racer"
+gem "mini_racer", platforms: :ruby
 
 gem "autoprefixer-rails"
 
@@ -94,14 +93,14 @@ group :development, :test do
 end
 
 group :test do
-  gem "capybara", "2.18.0"
+  gem "capybara"
   gem "capybara-screenshot"
   gem "coveralls", require: false
   gem "database_cleaner"
   gem "generator_spec"
   gem "launchy"
   gem "rails_best_practices"
-  gem "rspec-rails", "3.7.2"
+  gem "rspec-rails"
   gem "selenium-webdriver"
-  gem "webdrivers", "~> 4.0"
+  gem "webdrivers", "3.9.4"
 end