Release 2.21.1

Author: Krinkle

package.json

@@ -2,11 +2,11 @@
   "name": "qunit",
   "title": "QUnit",
   "description": "The powerful, easy-to-use testing framework.",
-  "version": "2.21.1-pre",
+  "version": "2.21.1",
   "homepage": "https://qunitjs.com",
   "author": {
     "name": "OpenJS Foundation and other contributors",
-    "url": "https://github.com/qunitjs/qunit/blob/main/AUTHORS.txt"
+    "url": "https://github.com/qunitjs/qunit/blob/2.21.1/AUTHORS.txt"
   },
   "repository": {
     "type": "git",