Gitpod startup fails due to PHP >=8.0.2 being required but PHP 7.4.25 is used

[kmbremner]

Describe the bug
The Gitpod quickstart for this repo fails because symfony/deprecation-contracts requires php >=8.0.2 and the project is using php 7.4.25.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://github.com/druxt/quickstart-druxt-site-contentacms
2. Under Quickstart, click on "Open in Gitpod"
3. Wait for the Gitpod build
4. See error:

Fatal error: Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 8.0.2". You are running 7.4.25. in /var/www/html/vendor/composer/platform_check.php on line 24
Failed to run drush si -y --account-pass=admin --site-name=quickstart-druxt-site-contenta contenta_jsonapi: exit status 255

Expected behavior
The Gitpod should run and build without error.