Adjusts Run Post Install

github_changelog_generator.gemspec

@@ -16,8 +16,8 @@ Gem::Specification.new do |spec|
   spec.summary = "Script, that automatically generate changelog from your tags, issues, labels and pull requests."
   spec.description = "Changelog generation has never been so easy. Fully automate changelog generation - this gem generate change log file based on tags, issues and merged pull requests from Github issue tracker."
   spec.homepage = "https://github.com/skywinder/Github-Changelog-Generator"
-  spec.license       = "MIT"
-  spec.extensions  = "ext/mkrf_conf.rb"
+  spec.license = "MIT"
+  spec.extensions = ["Rakefile"]
 
   spec.files = `git ls-files -z`.split("\x0")
   spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }