chore: manually add assets

spec/dummy/app/assets/builds/dashboard/cable.js

@@ -0,0 +1,17 @@
+(() => {
+  var __getOwnPropNames = Object.getOwnPropertyNames;
+  var __commonJS = (cb, mod) => function __require() {
+    return mod || (0, cb[__getOwnPropNames(cb)[0]])((mod = { exports: {} }).exports, mod), mod.exports;
+  };
+
+  // app/javascript/cable.js
+  var require_cable = __commonJS({
+    "app/javascript/cable.js"(exports) {
+      (function() {
+        this.App || (this.App = {});
+        App.cable = ActionCable.createConsumer();
+      }).call(exports);
+    }
+  });
+  require_cable();
+})();