PHP8 Version Trouble

Don't know why this check is failing. I've got Homebrew installed in `/opt/homebrew` on an M1 Mac, don't know if that's related.

```
qd@ariadne ~ % forge

Box Requirements Checker
========================

> Using PHP 8.0.3
> PHP is using the following php.ini file:
/opt/homebrew/etc/php/8.0/php.ini

> Checking Box requirements:
E.

[ERROR] Your system is not ready to run the application.

Fix the following mandatory requirements:
=========================================

* The application requires the version "^7.3" or greater.
```