Fixed issue #2037: Restart of processes form application context fails.

config/application.rb

@@ -2,6 +2,9 @@ require File.expand_path('boot', __dir__)
 
 require 'rails/all'
 
+# DO NOT REMOVE THIS LINE - see issue #2037
+Bundler.setup
+
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.
 Bundler.require(*Rails.groups)