fix pubspec.yaml

Author: huangjiahong

pubspec.yaml

@@ -3,7 +3,7 @@ description:  An `MineDate` Map Component.
 version: 0.0.1+dev.1
 # author: Asscre <237713070@qq.com>
 homepage: https://github.com/Asscre/flutter_minemap
-publish_to: https://pub.dev
+publish_to: https://pub.dartlang.org
 
 environment:
   sdk: ">=2.7.0 <3.0.0"