Lessen complexity of closest_setting method

app/models/project.rb

@@ -2251,10 +2251,7 @@ class Project < ApplicationRecord
   end
 
   def closest_setting(name)
-    setting = read_attribute(name)
-    setting ||= closest_namespace_setting(name)
-    setting ||= Gitlab::CurrentSettings.send(name) # rubocop:disable GitlabSecurity/PublicSend
-    setting
+    read_attribute(name) || closest_namespace_setting(name) || app_settings_for(name)
   end
 
   private
@@ -2266,6 +2263,10 @@ class Project < ApplicationRecord
       .try(name)
   end
 
+  def app_settings_for(name)
+    Gitlab::CurrentSettings.send(name) # rubocop:disable GitlabSecurity/PublicSend
+  end
+
   def merge_requests_allowing_collaboration(source_branch = nil)
     relation = source_of_merge_requests.opened.where(allow_collaboration: true)
     relation = relation.where(source_branch: source_branch) if source_branch