update the badge for the required PHP version

Author: michalsn

README.md

@@ -7,7 +7,7 @@ A task scheduler for CodeIgniter 4.
 [![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)
+![PHP](https://img.shields.io/badge/PHP-%5E8.1-blue)
 ![CodeIgniter](https://img.shields.io/badge/CodeIgniter-%5E4.1-blue)
 ![License](https://img.shields.io/badge/License-MIT-blue)
 

docs/index.md

@@ -11,7 +11,7 @@ information, which provides a convenient way of storing settings in the database
 
 ### Requirements
 
-![PHP](https://img.shields.io/badge/PHP-%5E7.4-red)
+![PHP](https://img.shields.io/badge/PHP-%5E8.1-red)
 ![CodeIgniter](https://img.shields.io/badge/CodeIgniter-%5E4.1-red)
 
 ### Quickstart