Fix JSX in readme (#2512)

An unclosed tag was resulting in some broken syntax highlighting.

readme.md

@@ -353,7 +353,7 @@ export default () => (
 // pages/index.js
 import Link from 'next/link'
 export default () => (
-  <div>Click <Link href='/about'><img src="/static/image.png"></Link></div>
+  <div>Click <Link href='/about'><img src="/static/image.png" /></Link></div>
 )
 ```
 
@@ -1132,4 +1132,4 @@ Please see our [contributing.md](./contributing.md)
 - Naoyuki Kanezawa ([@nkzawa](https://twitter.com/nkzawa)) – ▲ZEIT
 - Tony Kovanen ([@tonykovanen](https://twitter.com/tonykovanen)) – ▲ZEIT
 - Guillermo Rauch ([@rauchg](https://twitter.com/rauchg)) – ▲ZEIT
-- Dan Zajdband ([@impronunciable](https://twitter.com/impronunciable)) – Knight-Mozilla / Coral Project
\ No newline at end of file
+- Dan Zajdband ([@impronunciable](https://twitter.com/impronunciable)) – Knight-Mozilla / Coral Project