Add release summary helper (#5)

Author: jbeckwith-oai

.changeset/release-summary-helper.md

@@ -0,0 +1,5 @@
+---
+"demo-ruby-gem": patch
+---
+
+Add a release summary helper for demo output.

lib/demo_ruby_gem.rb

@@ -16,4 +16,8 @@ def self.second_feature_flag
   def self.release_pr_feature_flag
     :changesets_ruby_provider_release_pr_demo
   end
+
+  def self.release_summary
+    "demo-ruby-gem #{VERSION}"
+  end
 end