[meta] 4.0 beta blockers

Problem/Motivation

Follow-up from 📌 Create 4.x branch that uses Package Manager from core Active .

Opening this to track any blockers to removing package_manager from the code base.

I think once package_manager is beta in Drupal core (see 🌱 Drupal 10 Core Roadmap for Automatic Updates Active for blocking issues), it should be OK to release a 4.0 beta.

Seems like one additional blocker to a beta release would be checking whether automatic updates can update itself from 3.x to 4.x

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes