Merge branch 'proxy_instance_guid' of https://git.erp5.org/repos/slapos.core into proxy_instance_guid

This is workaround for some bugs in setters, which are irrelevant for testing.

Originally system would create compensation movements in case of difference on
frozen movements, but this is explicitely disabled.

The history of Hosting Subscription is fully written before alarm can chance to
run.

Forgot to remove the script.

The HostingSubscription_requestUpdateOpenSaleOrder is required (and tested).