Refactor admin settings routes

This is much cleaner, and semantically more correct.

spec/features/admin/settings_spec.rb

@@ -23,35 +23,35 @@ RSpec.describe 'Admin/global settings', type: :feature do
     scenario "Opening service settings shows page for first service" do
       visit admin_settings_services_path
 
-      expect(current_url).to eq(admin_settings_services_url(params: { s: "btcpay" }))
+      expect(current_url).to eq(admin_settings_service_url("btcpay"))
     end
 
     scenario "View service settings" do
-      visit admin_settings_services_path(params: { s: "ejabberd" })
+      visit admin_settings_service_path("ejabberd")
 
       expect(page).to have_content("Enable ejabberd integration")
       expect(page).to have_field("API URL", with: "http://xmpp.example.com/api")
     end
 
     scenario "Disable a service integration" do
-      visit admin_settings_services_path(params: { s: "ejabberd" })
+      visit admin_settings_service_path("ejabberd")
       expect(page).to have_checked_field("setting[ejabberd_enabled]")
 
       uncheck "setting[ejabberd_enabled]"
       click_button "Save"
 
-      expect(current_url).to eq(admin_settings_services_url(params: { s: "ejabberd" }))
+      expect(current_url).to eq(admin_settings_service_url("ejabberd"))
       expect(page).to_not have_checked_field("setting[ejabberd_enabled]")
       expect(page).to_not have_field("API URL", disabled: true)
     end
 
     scenario "Resettable fields" do
-      visit admin_settings_services_path(params: { s: "ejabberd" })
+      visit admin_settings_service_path("ejabberd")
       expect(page).to have_field("API URL", with: "http://xmpp.example.com/api")
       expect(page).to_not have_css('input#setting_ejabberd_api_url+button')
 
       Setting.ejabberd_api_url = "http://example.com/foo"
-      visit admin_settings_services_path(params: { s: "ejabberd" })
+      visit admin_settings_service_path("ejabberd")
       expect(page).to have_field("API URL", with: "http://example.com/foo")
       expect(page).to have_css('input#setting_ejabberd_api_url+button')
     end