[BUG] Package php-token-stream abandoned

Created by: strarsis

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?

Description

The package/project php-token-stream has been abandoned, hence a replacement is needed (but no replacement is stated on the php-token-stream project page).

openapi-generator version

1.0.18-4.3.1

Steps to reproduce

Run composer install or composer update for the generated project and a deprecation notice is logged for the package php-token-stream

Suggest a fix

A maintained and stable replacement package has to be found.