chore(tests): added websocket to global when not already done (nodejs20)

Author: rolljee

test/setup.js

@@ -1,9 +1,16 @@
 "use strict";
 
 /**
- * Ensure a global XMLHttpRequest binding exists so strict-mode tests can
- * reassign it without throwing ReferenceError in Node.
+ * Ensure global bindings exist so strict-mode tests can reassign them
+ * without throwing ReferenceError in Node.
  */
 if (typeof global.XMLHttpRequest === "undefined") {
   global.XMLHttpRequest = undefined;
 }
+
+// Define a writable global binding for WebSocket when Node does not provide one
+if (typeof WebSocket === "undefined") {
+  /* eslint-disable no-var */
+  var WebSocket = undefined; // creates the global binding
+  /* eslint-enable no-var */
+}