This is not enabled by default in the core version for performance reasons,
as Vector/CowData are used in critical code paths where not zero'ing memory
which is going to be set later on can be important.
But for bindings / the scripting API, we make zero the new items by default
(which already happened for built types like Vector3, etc., but not for
trivial types like int, float).
Fixes#43033.
Co-authored-by: David Hoppenbrouwers <david@salt-inc.org>
c717d5c64b