Fix Appveyor badge url

Summary: Pull Request resolved: react#21159

Differential Revision: D9928127

Pulled By: hramos

fbshipit-source-id: e6cf099186fffc79ebf463897b55e0c3e728f3f5

Author: hramos

README.md

@@ -1,4 +1,5 @@
-# [React Native](https://facebook.github.io/react-native/) ·  [![Circle CI Status](https://circleci.com/gh/facebook/react-native.svg?style=shield)](https://circleci.com/gh/facebook/react-native) [![Build status](https://ci.appveyor.com/api/projects/status/github/facebook/react-native?branch=master&svg=true)](https://ci.appveyor.com/project/facebook/react-native/branch/master) [![npm version](https://badge.fury.io/js/react-native.svg)](https://badge.fury.io/js/react-native) [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](CONTRIBUTING.md#pull-requests)
+# [React Native](https://facebook.github.io/react-native/) ·  [![Circle CI Status](https://circleci.com/gh/facebook/react-native.svg?style=shield)](https://circleci.com/gh/facebook/react-native) [![Build status](https://ci.appveyor.com/api/projects/status/g8d58ipi3auqdtrk/branch/master?svg=true
+)](https://ci.appveyor.com/project/facebook/react-native/branch/master) [![npm version](https://badge.fury.io/js/react-native.svg)](https://badge.fury.io/js/react-native) [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](CONTRIBUTING.md#pull-requests)
 
 Learn once, write anywhere: Build mobile apps with React.