Prevent #update_daemon from running for instance domains

Since this is not needed, and it would produce errors because there is
no project

app/models/pages_domain.rb

@@ -220,6 +220,8 @@ class PagesDomain < ApplicationRecord
 
   # rubocop: disable CodeReuse/ServiceClass
   def update_daemon
+    return if domain_type_instance?
+
     ::Projects::UpdatePagesConfigurationService.new(project).execute
   end
   # rubocop: enable CodeReuse/ServiceClass

spec/models/pages_domain_spec.rb

@@ -315,6 +315,14 @@ describe PagesDomain do
   end
 
   describe '#update_daemon' do
+    context 'when domain_type is instance' do
+      it 'does nothing' do
+        expect(Projects::UpdatePagesConfigurationService).not_to receive(:new)
+
+        create(:pages_domain, domain_type: :instance)
+      end
+    end
+
     it 'runs when the domain is created' do
       domain = build(:pages_domain)