Exclude Makefile from generated output

Author: timsneath

_config.yml

@@ -2,7 +2,7 @@ url: https://swift.org
 title: Swift.org
 description: "Swift is a general-purpose programming language built using a modern approach to safety, performance, and software design patterns."
 timezone: America/Lower_Princes
-exclude: ["README.md", "config.ru", "Gemfile", "Gemfile.lock", "Procfile", "vendor", "get-started/storybook"]
+exclude: ["README.md", "config.ru", "Gemfile", "Gemfile.lock", "Procfile", "vendor", "get-started/storybook", "Makefile"]
 safe: false
 future: true