Changes to common rails wrapper script

rails

#!/usr/bin/env ruby

# This file is located at `bin/rails`

# Load the 'switch_user_and_exec' routine:
require_relative '../config/switch_user_and_exec'

begin
  load File.expand_path('../spring', __FILE__)
rescue LoadError => e
  raise unless e.message.include?('spring')
end
APP_PATH = File.expand_path('../config/application', __dir__)
require_relative '../config/boot'
require 'rails/commands'

switch_user_and_exec.rb

# This file is located at `config/switch_user_and_exec.rb`

require 'etc'
info = Etc.getpwuid

if info.name == 'root' && (target_user = ENV['DEVELOPER_USER'])
  puts "Switching from 'root' user to '#{target_user}'..."
  exec 'su-exec', target_user, $0, *$*
end