Remove strange conditional in generate:app task

The `bindir` is rspec-rails' one. We want to run `bundle binstubs` in
the `tmp/example_app` project so the conditional `if test, 'd', bindir`
is useless.

Rakefile

@@ -29,21 +29,19 @@ namespace :generate do
       sh "rm -f #{bindir}/rails"
       sh "bundle exec rails new ./tmp/example_app --skip-javascript --skip-sprockets --skip-git --skip-test-unit --skip-bundle --template=example_app_generator/generate_app.rb"
 
-      if test 'd', bindir
-        in_example_app do
-          sh "./travis_retry_bundle_install.sh 2>&1"
-          # Rails 4 cannot use a `rails` binstub generated by Bundler
-          sh "bundle binstubs rspec-core rake --force"
-          sh "bundle binstubs railties" unless File.exist?("bin/rails")
-
-          application_file = File.read("config/application.rb")
-          sh "rm config/application.rb"
-          File.open("config/application.rb", "w") do |f|
-            f.write application_file.gsub(
-              "config.assets.enabled = true",
-              "config.assets.enabled = false"
-            )
-          end
+      in_example_app do
+        sh "./travis_retry_bundle_install.sh 2>&1"
+        # Rails 4 cannot use a `rails` binstub generated by Bundler
+        sh "bundle binstubs rspec-core rake --force"
+        sh "bundle binstubs railties" unless File.exist?("bin/rails")
+
+        application_file = File.read("config/application.rb")
+        sh "rm config/application.rb"
+        File.open("config/application.rb", "w") do |f|
+          f.write application_file.gsub(
+            "config.assets.enabled = true",
+            "config.assets.enabled = false"
+          )
         end
       end
     end