add world.use_nodes=True to survive cleanup

[Mxbonn]

This line is required to survive a bproc.cleanup()
Similar to

BlenderProc/blenderproc/python/renderer/RendererUtility.py

Line 829 in 1ddf570

world.use_nodes = True

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[cornerfarmer]

Hey @Mxbonn,

thanks a lot for the PR. I found that recreating the world nodes directly in clean_up() makes more sense (see #1166). This should also cover your issue, but let me know if that is not the case.