Use Gitlab::CurrentSettings instead of current_application_settings

app/models/project_auto_devops.rb

 class ProjectAutoDevops < ActiveRecord::Base
-  include Gitlab::CurrentSettings
-
   belongs_to :project
   scope :enabled, -> { where(enabled: true) }
@@ -9,7 +7,7 @@ class ProjectAutoDevops < ActiveRecord::Base
   validates :domain, allow_blank: true, hostname: { allow_numeric_hostname: true }
   def instance_domain
-    current_application_settings.auto_devops_domain
+    Gitlab::CurrentSettings.auto_devops_domain
   end
   def has_domain?

spec/features/admin/admin_settings_spec.rb

@@ -52,8 +52,8 @@ feature 'Admin updates settings' do
     fill_in 'Auto devops domain', with: 'domain.com'
     click_button 'Save'
-    expect(current_application_settings.auto_devops_enabled?).to be true
-    expect(current_application_settings.auto_devops_domain).to eq('domain.com')
+    expect(Gitlab::CurrentSettings.auto_devops_enabled?).to be true
+    expect(Gitlab::CurrentSettings.auto_devops_domain).to eq('domain.com')
     expect(page).to have_content "Application settings saved successfully"
   end

spec/models/project_auto_devops_spec.rb

@@ -20,7 +20,7 @@ describe ProjectAutoDevops do
       context 'when there is an instance domain specified' do
         before do
-          stub_application_setting(auto_devops_domain: 'example.com')
+          allow(Gitlab::CurrentSettings).to receive(:auto_devops_domain).and_return('example.com')
         end
         it { expect(auto_devops).to have_domain }
@@ -28,7 +28,7 @@ describe ProjectAutoDevops do
       context 'when there is no instance domain specified' do
         before do
-          stub_application_setting(auto_devops_domain: nil)
+          allow(Gitlab::CurrentSettings).to receive(:auto_devops_domain).and_return(nil)
         end
         it { expect(auto_devops).not_to have_domain }
@@ -52,7 +52,7 @@ describe ProjectAutoDevops do
       context 'when there is an instance domain specified' do
         before do
-          stub_application_setting(auto_devops_domain: 'example.com')
+          allow(Gitlab::CurrentSettings).to receive(:auto_devops_domain).and_return('example.com')
         end
         it { expect(auto_devops.variables).to include(domain_variable) }
@@ -60,7 +60,7 @@ describe ProjectAutoDevops do
       context 'when there is no instance domain specified' do
         before do
-          stub_application_setting(auto_devops_domain: nil)
+          allow(Gitlab::CurrentSettings).to receive(:auto_devops_domain).and_return(nil)
         end
         it { expect(auto_devops.variables).not_to include(domain_variable) }