Remove integrations from VALID_SETTING_PANELS

Since it's fully migrated to new integrations, we don't need
the old actions anymore.

app/controllers/admin/application_settings_controller.rb

@@ -16,7 +16,7 @@ class Admin::ApplicationSettingsController < Admin::ApplicationController
     push_frontend_feature_flag(:ci_instance_variables_ui, default_enabled: true)
   end
 
-  VALID_SETTING_PANELS = %w(general integrations repository
+  VALID_SETTING_PANELS = %w(general repository
                             ci_cd reporting metrics_and_profiling
                             network preferences).freeze
 

spec/controllers/admin/application_settings_controller_spec.rb

@@ -142,7 +142,7 @@ RSpec.describe Admin::ApplicationSettingsController do
     end
 
     describe 'verify panel actions' do
-      (Admin::ApplicationSettingsController::VALID_SETTING_PANELS - ['integrations']).each do |valid_action|
+      Admin::ApplicationSettingsController::VALID_SETTING_PANELS.each do |valid_action|
         it_behaves_like 'renders correct panels' do
           let(:action) { valid_action }
         end