[PP-1] Update \Drupal\package_manager\ComposerUtility::__construct() typehint to \Composer\PartialComposer once composer ^2.3 is required

Problem/Motivation

Discovered by @phenaproxima in #3314137: Make Automatic Updates Drupal 10-compatible.

This should happen after #3321474: Adopt PHP 8.1-only capabilities such as constructor property promotion + drop BC layers, which means that at that point this will not be an API change, but a purely internal change.

\Composer\Composer|\Composer\PartialComposer should be narrowed to \Composer\PartialComposer.

Steps to reproduce

N/A

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes