Update OVM to `mesh_copying` and copy mesh instead of raw pointer.

Fixes OpenFlipper-Free#143 (closed). Warning: references non-master commit in OVM, cf https://www.graphics.rwth-aachen.de:9000/OpenVolumeMesh/OpenVolumeMesh/merge_requests/24

Corresponding OF CI: https://www.graphics.rwth-aachen.de:9000/OpenFlipper-Free/OpenFlipper-Free/pipelines/6160