Update index-test.js

Author: bradzacher

__tests__/index-test.js

@@ -40,8 +40,10 @@ test('schemas', (t) => {
 });
 
 test('plugin referentially equal to prevent flat config issues', (t) => {
-  for (const config in Object.keys(plugin.flatConfigs)) {
-    t.equal(plugin, plugin.flatConfigs[config].plugins['jsx-a11y'], `${config.name}'s plugin reference is referentially equal to the top-level export`);
+  const keys = Object.keys(plugin.flatConfigs);
+  for (let i = 0; i < keys.length; i += 1) {
+    const config = plugin.flatConfigs[keys[i]];
+    t.equal(plugin, config.plugins['jsx-a11y'], `${config.name}'s plugin reference is referentially equal to the top-level export`);
   }
   t.end();
 });