settings: fix recursive traversal in to_env_dict
settings: fix recursive traversal in to_env_dict

This fixes as _HUGE_ error in the recursive traversal strategy of to_env_dict. Before this fix, we simply would not be able to convert the settings to enything but the empty dictionary.

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PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild