fix typo: delete comma

extension.json

@@ -3,7 +3,7 @@
 	"version": "1.4.0",
 	"author": [
 		"Jack Phoenix",
-		"Qiuwen Baike Contributors",
+		"Qiuwen Baike Contributors"
 	],
 	"license-name": "GPL-2.0-or-later",
 	"url": "https://git.qiuwen.wiki/qiuwen/NewSignupPage",