Add GitHub Actions badge

Author: ThomWright

README.md

@@ -1,6 +1,6 @@
 # Postgres migrations
 
-[![Travis](https://img.shields.io/travis/ThomWright/postgres-migrations.svg)](https://travis-ci.org/ThomWright/postgres-migrations)
+![GitHub Actions](https://github.com/ThomWright/postgres-migrations/actions/workflows/node.js.yml/badge.svg)
 [![npm](https://img.shields.io/npm/v/postgres-migrations.svg)](https://www.npmjs.com/package/postgres-migrations)
 [![David](https://img.shields.io/david/ThomWright/postgres-migrations.svg)](https://david-dm.org/ThomWright/postgres-migrations)
 [![David](https://img.shields.io/david/dev/ThomWright/postgres-migrations.svg)](https://david-dm.org/ThomWright/postgres-migrations)