Rename workflow from "Go Build and Release" to "Unit tests" and update README badge link

Author: ceelsoin

.github/workflows/tests.yaml

@@ -1,4 +1,4 @@
-name: Go Build and Release
+name: Unit tests
 
 on:
   push:

README.md

@@ -1,7 +1,7 @@
 
 # go-qs
 
-[![Go Reference](https://pkg.go.dev/badge/github.com/globocom/go-qs.svg)](https://pkg.go.dev/github.com/globocom/go-qs)
+[![Go Reference](https://pkg.go.dev/badge/github.com/globocom/go-qs.svg)](https://pkg.go.dev/github.com/globocom/go-qs) [![Unit tests](https://github.com/globocom/go-qs/actions/workflows/tests.yaml/badge.svg)](https://github.com/globocom/go-qs/actions/workflows/tests.yaml)
 
 > Parse and decode URL query strings into nested Go data structures. Compatible with [javascript qs](npmjs.com/package/qs).