FEATURE: API Scope for latest.rss feed (#21906)

Adds an API scope for the `/latest.rss` route.

https://meta.discourse.org/t/188480

app/models/api_key_scope.rb

@@ -6,7 +6,7 @@ class ApiKeyScope < ActiveRecord::Base
 
   class << self
     def list_actions
-      actions = %w[list#category_feed list#category_default]
+      actions = %w[list#category_feed list#category_default list#latest_feed]
 
       %i[latest unread new top].each { |f| actions.concat(["list#category_#{f}", "list##{f}"]) }
 

spec/requests/admin/api_controller_spec.rb

@@ -434,6 +434,8 @@ RSpec.describe Admin::ApiController do
           "invites",
           "wordpress",
         )
+
+        expect(scopes["topics"].any? { |h| h["urls"].include?("/latest.rss (GET)") }).to be_truthy
       end
     end