docs(readme): fix spacing issue on the Slack logo (#2777)

README.md

@@ -5,7 +5,8 @@
 [![Total npm downloads](https://img.shields.io/npm/dt/axe-core.svg)](https://www.npmjs.com/package/axe-core)
 [![Commits](https://img.shields.io/github/commit-activity/y/dequelabs/axe-core.svg)](https://github.com/dequelabs/axe-core/commits/develop)
 [![GitHub contributors](https://img.shields.io/github/contributors/dequelabs/axe-core.svg)](https://github.com/dequelabs/axe-core/graphs/contributors)
-[![Join our Slack chat](https://img.shields.io/badge/slack-chat-purple.svg?logo=slack)](https://accessibility.deque.com/axe-community)[![Package Quality](http://npm.packagequality.com/shield/axe-core.svg)](http://packagequality.com/#?package=axe-core)
+[![Join our Slack chat](https://img.shields.io/badge/slack-chat-purple.svg?logo=slack)](https://accessibility.deque.com/axe-community)
+[![Package Quality](http://npm.packagequality.com/shield/axe-core.svg)](http://packagequality.com/#?package=axe-core)
 
 Axe is an accessibility testing engine for websites and other HTML-based user interfaces. It's fast, secure, lightweight, and was built to seamlessly integrate with any existing test environment so you can automate accessibility testing alongside your regular functional testing.