binstubs: revert to rails binstubs (77b42310)

Silence complaints from rails about using Bundler-generated binstubs.

bin/rake

@@ -1,29 +1,4 @@
 #!/usr/bin/env ruby
-# frozen_string_literal: true
-
-#
-# This file was generated by Bundler.
-#
-# The application 'rake' is installed as part of a gem, and
-# this file is here to facilitate running it.
-#
-
-require "pathname"
-ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
-  Pathname.new(__FILE__).realpath)
-
-bundle_binstub = File.expand_path("../bundle", __FILE__)
-
-if File.file?(bundle_binstub)
-  if File.read(bundle_binstub, 150) =~ /This file was generated by Bundler/
-    load(bundle_binstub)
-  else
-    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
-Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
-  end
-end
-
-require "rubygems"
-require "bundler/setup"
-
-load Gem.bin_path("rake", "rake")
+require_relative '../config/boot'
+require 'rake'
+Rake.application.run