Build: Enforce ECMAScript 5 in tests via ESLint

Fixes gh-5542
Closes gh-5563

(cherry picked from commit d74fc265de2bca3060da2e6f5ec00371b16e43ca)

diff --git a/eslint.config.js b/eslint.config.js
index 37dc57bf31596be6b57831a2ec38803795886da4..b1a23786500724e7c386a2e73db8ee2ebb3fe296 100644 (file)
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -122,11 +122,13 @@ module.exports = [
                        "test/data/core/jquery-iterability-transpiled.js"
                ],
                languageOptions: {
-                       ecmaVersion: 2015,
+                       ecmaVersion: 5,
                        sourceType: "script",
                        globals: {
                                ...globals.browser,
                                require: false,
+                               Promise: false,
+                               Symbol: false,
                                trustedTypes: false,
                                QUnit: false,
                                ajaxTest: false,