Cannot install Starshot due to PHP incompatibility

Problem / Motivation

1. From the SimplyTest.me homepage, click the "Starshot" button.
2. It starts to build, but soon fails with this error:

Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Root composer.json requires drupal/core-recommended ^11.x-dev -> satisfiable by drupal/core-recommended[11.x-dev].
    - drupal/core 11.x-dev requires php >=8.3.0 -> your php version (8.2.25) does not satisfy that requirement.
    - drupal/core-recommended 11.x-dev requires drupal/core 11.x-dev -> satisfiable by drupal/core[11.x-dev].

It needs at least PHP 8.3, but 8.2 is installed.