title: Laravel Forge - Upgrading project to Laravel 8 needs PHP 7.4
body: <p>I recently migrated a Forge-hosted project to Laravel 8.x.  The deployment script fails when running <code>composer install</code>, all of the messages related to having the wrong PHP version:</p>
  <pre><code>Installing dependencies (including require-dev) from lock file
  Your requirements could not be resolved to an installable set of packages.
  
    Problem 1
      - This package requires php ^7.4 but your PHP version (7.3.26) does not satisfy that requirement.
    Problem 2
      - Installation request for lcobucci/clock 2.0.0 -&gt; satisfiable by lcobucci/clock[2.0.0].
      - lcobucci/clock 2.0.0 requires php ^7.4 || ^8.0 -&gt; your PHP version (7.3.26) does not satisfy that requirement.
  ...
  </code></pre>
  <h2>I did this though.</h2>
  <p>At least according to the <a href="https://forge.laravel.com/docs/1.0/servers/php.html" rel="nofollow noreferrer">documentation</a>.  PHP 7.4 is selected in Meta &gt; PHP Version for this site.  In PHP Management, 7.4 is default and is updated to latest patch.
  <a href="https://i.stack.imgur.com/Tuavl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Tuavl.png" alt="enter image description here" /></a></p>
  <p>I restarted PHP, then Nginx, then the entire server, none of it worked.</p>
  <p>Via SSH it is using 7.3.26:</p>
  <pre><code>forge@mistaken-identity:~$ php -v
  PHP 7.3.26-1+ubuntu18.04.1+deb.sury.org+1 (cli) (built: Jan 13 2021 08:00:44) ( NTS )
  Copyright (c) 1997-2018 The PHP Group
  Zend Engine v3.3.26, Copyright (c) 1998-2018 Zend Technologies
      with Zend OPcache v7.3.26-1+ubuntu18.04.1+deb.sury.org+1, Copyright (c) 1999-2018, by Zend Technologies
  </code></pre>
  <p>Is Forge's PHP management API broken, or just on my server?   I would like to be able to set PHP version on a per-site basis.  How can I fix this?</p>