Handle issue model to reference through the namespace

What does this MR do and why?

This MR is handling work items references both apt project and group level. It is extracted out of the original bigger MR !111664 (merged) that addresses work item creation at group level.

Some of the challenges with handling references both at group and project level is that we need to preload the namespace as well and that can also add an additional query to fetch the project namespace.

re #392992 (closed) re &8308

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