add badges (#144)

Author: michalsn

README.md

@@ -2,6 +2,14 @@
 
 A task scheduler for CodeIgniter 4.
 
+[![PHPUnit](https://github.com/codeigniter4/tasks/actions/workflows/phpunit.yml/badge.svg)](https://github.com/codeigniter4/tasks/actions/workflows/phpunit.yml)
+[![PHPStan](https://github.com/codeigniter4/tasks/actions/workflows/phpstan.yml/badge.svg)](https://github.com/codeigniter4/tasks/actions/workflows/phpstan.yml)
+[![Deptrac](https://github.com/codeigniter4/tasks/actions/workflows/deptrac.yml/badge.svg)](https://github.com/codeigniter4/tasks/actions/workflows/deptrac.yml)
+[![Coverage Status](https://coveralls.io/repos/github/codeigniter4/tasks/badge.svg?branch=develop)](https://coveralls.io/github/codeigniter4/tasks?branch=develop)
+
+![PHP](https://img.shields.io/badge/PHP-%5E7.4-blue)
+![CodeIgniter](https://img.shields.io/badge/CodeIgniter-%5E4.1-blue)
+
 ## Installation
 
 Install via Composer: