Blender Git Loki

Fix T74397: Crash after undoing quadriflow remesh on duplicate with armature deform

The issue was that we were creating temporary mesh copies and storing
them in bmain and then later using BKE_mesh_nomain_to_mesh which would
add them to bmain once more (duplicates).

This would lead to crashes later as the custom data of the mesh could be
trashed quite easily.