get_all_replicas segfaults

I've not narrowed it down much, but it usually works fine locally when the document is not in a collection. So I suspected this is the issue but need to verify. I have now seen it in the integration tests for 6.0.3, so I suspect it happens intermittently, and maybe isn't something having to do with collections.

This was put into 3.0.0 for now. Lets first better characterize the segfault and when it does and doesn't happen, then decide how to prioritize