Provide a 'Changelog' link on rubygems.org/gems/net-http

By providing a 'changelog_uri' in the metadata of the gemspec a
'Changelog' link will be shown on https://rubygems.org/gems/net-http
which makes it quick and easy for someone to check on the changes
introduced with a new version.

Details of this functionality can be found on https://guides.rubygems.org/specification-reference/#metadata

Author: mark-young-atg

net-http.gemspec

@@ -24,6 +24,7 @@ Gem::Specification.new do |spec|
   spec.required_ruby_version = Gem::Requirement.new(">= 2.6.0")
   spec.licenses      = ["Ruby", "BSD-2-Clause"]
 
+  spec.metadata["changelog_uri"] = spec.homepage + "/releases"
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage