docs(README): fix typo

Narretz · Narretz · commit 7477fbec6175 · 2016-04-08T19:00:31.000+02:00
diff --git a/README.md b/README.md
@@ -22,7 +22,7 @@ piece of cake. Best of all? It makes development fun!
 
 Building AngularJS
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-[Once you have set up your environment](httpd://docs.angularjs.org/misc/contribute), just run:
+[Once you have set up your environment](https://docs.angularjs.org/misc/contribute), just run:
 
     grunt package
 
