Automatically delete checkpoints

Problem/Motivation

This is a really a core issue. But once modules are updated previous checkpoints essentially become useless as it would be potentially disastrous to roll back to them.
But core doesn't surface checkpoints so without this module nobody cares about them. We can fix it fast then wait for the patch to land in core.

Steps to reproduce

1. Update a module that has config schema changes.
2. Revert to a checkpoint from before which will undo the update hook.
3. Module expects updated config, but it is now broken.

Proposed resolution

delete all checkpoints when modules are updated.

Remaining tasks

patch
patch core
remove patch again.

User interface changes

Old checkpoints are gone

API changes

none

Data model changes

none