Rename test suite

Author: Antonio Ribeiro

.github/workflows/laravel.yml renamed to .github/workflows/phpunit.yml

@@ -1,4 +1,4 @@
-name: Tests
+name: PHPUnit
 
 on:
   push:

README.md

@@ -7,7 +7,7 @@
 <p align="center">
     <a href="https://packagist.org/packages/pragmarx/countries"><img alt="Latest Stable Version" src="https://img.shields.io/packagist/v/pragmarx/countries.svg?style=flat-square"></a>
     <a href="/antonioribeiro/countries/blob/master/LICENSE.md"><img alt="License" src="https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square"></a>
-    <a href="https://github.com/antonioribeiro/countries/actions"><img alt="Build" src="https://img.shields.io/github/actions/workflow/status/antonioribeiro/countries/laravel.yml?style=flat-square"></a>
+    <a href="https://github.com/antonioribeiro/countries/actions"><img alt="Build" src="https://img.shields.io/github/actions/workflow/status/antonioribeiro/countries/phpunit.yml?style=flat-square"></a>
     <a href="https://github.com/antonioribeiro/countries/actions"><img alt="Static Analysis" src="https://img.shields.io/github/actions/workflow/status/antonioribeiro/countries/static-analysis.yml?style=flat-square&label=static-analysis"></a>
 </p>
 <p align="center">