Loosen core's require-dev constraints to allow higher major versions that work

Problem/Motivation

Currently, some of core's require-dev constraints constrain those packages to non-latest major versions. This prevents an application from installing both drupal/core-dev and other packages that might require later versions of the same dependencies. For example, core currently constrains symfony/filesystem to ^4.4, but Drush would like to be able to use symfony/filesystem v5 (see https://github.com/drush-ops/drush/pull/5264 which broke compatibility with drupal/core-dev and is about to be reverted until this issue is fixed).

Steps to reproduce

Proposed resolution

Broaden our require-dev constraints (e.g., change the symfony/filesystem one to ^4.4 || ^5.4 or maybe even ^4.4 || ^5.4 || ^6.1) where doing so still passes all of our tests (on the "updated deps" DrupalCI job).