State the default render offsets in the documentation

With 1.16.201, custom items can now have custom render offsets(at least when Holiday Creator Features is enabled), which control how the item appears when held(size, scale, and rotation). This is a good addition, and allows for more control over custom items, but there is one problem. The default values for render offsets aren't stated anywhere. This makes it annoying to use them, as there's no base you have to work off of. Sharing the default values would at least give us that though.