Update badge link for GitHub Actions

Author: mattpolzin

README.md

@@ -1,6 +1,6 @@
 [![sswg:sandbox|94x20](https://img.shields.io/badge/sswg-sandbox-lightgrey.svg)](https://github.com/swift-server/sswg/blob/master/process/incubation.md#sandbox-level) [![Swift 5.8+](http://img.shields.io/badge/Swift-5.8+-blue.svg)](https://swift.org)
 
-[![MIT license](http://img.shields.io/badge/license-MIT-lightgrey.svg)](http://opensource.org/licenses/MIT) ![Tests](https://github.com/mattpolzin/OpenAPIKit/workflows/Tests/badge.svg)
+[![MIT license](http://img.shields.io/badge/license-MIT-lightgrey.svg)](http://opensource.org/licenses/MIT) ![Tests](https://github.com/mattpolzin/OpenAPIKit/actions/workflows/tests.yml/badge.svg?branch=main)
 
 # OpenAPIKit <!-- omit in toc -->