[rubygems/rubygems] Fold a line that got out of hand

https://github.com/rubygems/rubygems/commit/49317d8beb

lib/rubygems/commands/setup_command.rb

@@ -411,8 +411,15 @@ By default, this RubyGems will install gem as:
     Dir.chdir("bundler") do
       built_gem = Gem::Package.build(bundler_spec)
       begin
-        installer = Gem::Installer.at(built_gem, env_shebang: options[:env_shebang], format_executable: options[:format_executable], force: options[:force], install_as_default: true, bin_dir: bin_dir, wrappers: true)
-        installer.install
+        Gem::Installer.at(
+          built_gem,
+          env_shebang: options[:env_shebang],
+          format_executable: options[:format_executable],
+          force: options[:force],
+          install_as_default: true,
+          bin_dir: bin_dir,
+          wrappers: true
+        ).install
       ensure
         FileUtils.rm_f built_gem
       end