When we deploy e.g. app/org.foo.bar/x86_64/stable, then we
also create a deploy/app/org.foo.bar/x86_64/stable ref pointing to
the latest deployed commit. We also remove it when an app is uninstalled.
This means that a prune operation will not delete objects that are deployed
(which would not save any space anyway). This is nice because this can
happen for instance when you flatpak update --no-deploy.
Fixes https://github.com/flatpak/flatpak/issues/2085Closes: #2563
Approved by: alexlarsson