Remove setting RAILS_ENV from RACK_ENV

Per #3200

Author: justin808

lib/install/bin/webpack

@@ -5,7 +5,7 @@ require "bundler/setup"
 require "webpacker"
 require "webpacker/webpack_runner"
 
-ENV["RAILS_ENV"] ||= ENV["RACK_ENV"] || "development"
+ENV["RAILS_ENV"] ||= "development"
 ENV["NODE_ENV"]  ||= "development"
 ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile", Pathname.new(__FILE__).realpath)
 

lib/install/bin/webpack-dev-server

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-ENV["RAILS_ENV"] ||= ENV["RACK_ENV"] || "development"
+ENV["RAILS_ENV"] ||= "development"
 ENV["NODE_ENV"]  ||= "development"
 
 require "pathname"

test/test_app/bin/webpack

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-ENV["RAILS_ENV"] ||= ENV["RACK_ENV"] || "development"
+ENV["RAILS_ENV"] ||= "development"
 ENV["NODE_ENV"] ||= ENV["RAILS_ENV"]
 
 require "pathname"

test/test_app/bin/webpack-dev-server

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-ENV["RAILS_ENV"] ||= ENV["RACK_ENV"] || "development"
+ENV["RAILS_ENV"] ||= "development"
 ENV["NODE_ENV"] ||= ENV["RAILS_ENV"]
 
 require "pathname"