Backup device manifest as artifact

Description

Issue(s)

https://gitlab.e.foundation/e/backlog/-/issues/5308

https://gitlab.e.foundation/e/devices/backlog/-/issues/137

Test procedures

Create a build here

https://gitlab.e.foundation/e/priv/os/build/-/pipelines

using backup-device-manifest-as-artifact branch

result artifact should include a device manifest .xml

Like in here:

https://gitlab.e.foundation/e/priv/os/build/-/jobs/291707

Check list

• Self review
• Test procedure explained