Update gem metadata (#42)

* Add source_code_uri to gem metadata

* Update metadata and CHANGELOG noting GitHub Releases usage

* Bump version to v8.0.0

Author: jgarber623

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+> [!NOTE]
+> From v8.0.0, changes are documented using [GitHub Releases](https://github.com/indieweb/webmention-client-ruby/releases). For a given release, metadata on RubyGems.org will link to that version's Release page.
+
 ## 7.0.0 / 2022-11-09
 
 - Refactor HTML and JSON parser classes (ec58206 and 6818c05)

lib/webmention/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Webmention
-  VERSION = "7.0.0"
+  VERSION = "8.0.0"
 end

webmention.gemspec

@@ -23,8 +23,9 @@ Gem::Specification.new do |spec|
 
   spec.metadata = {
     "bug_tracker_uri" => "#{spec.homepage}/issues",
-    "changelog_uri" => "#{spec.homepage}/blob/v#{spec.version}/CHANGELOG.md",
-    "rubygems_mfa_required" => "true"
+    "changelog_uri" => "#{spec.homepage}/releases/tag/v#{spec.version}",
+    "rubygems_mfa_required" => "true",
+    "source_code_uri" => "#{spec.homepage}/tree/v#{spec.version}"
   }
 
   spec.add_runtime_dependency "http", "~> 5.0"