fix: Real-time collaboration admin page: save button visible on read-only non-editable form (WP #69801)

modules/documents/app/components/documents/admin/collaboration_settings/settings_form_component.html.erb

@@ -61,7 +61,7 @@
           placeholder: Setting.collaborative_editing_hocuspocus_secret.present? ? "••••••••••••••••" : nil
         )
 
-        form.submit
+        form.submit unless none_writable_settings?
       end
     end
   else

modules/documents/spec/features/documents/admin/settings/document_collaboration_settings_spec.rb

@@ -186,6 +186,10 @@ RSpec.describe "Document collaboration settings admin",
                                  with: "",
                                  disabled: true)
     end
+
+    it "does not show a save button" do
+      expect(page).to have_no_button(I18n.t("button_save"))
+    end
   end
 
   context "with non-admin user" do