Ensure empty space rename/move set move request deep to true

When renaming a space with children page, we opt-in by default the checkbox to rename children: this translates in the API by having a request with a deep parameter set to true.
However, the API returns false by default when the deep parameter is not set.
And if there's no children page, currently we don't set that parameter at all: so any rename request of a space without children ends up having the deep parameter set to false.

This is a problem for Change Request where I'm using this parameter to know if it's the rename of a full space or not, to also refactor the request for creation in that space.

IMO we should always have the deep parameter set to true in such case: it shouldn't have any impact for standard pages in XWiki, but would avoid hack-ish checks in Change Request.