Error: Multiple chain IDs in chain: {'A', 'B'}

Hi there,

I've noticed you added this particular line:

https://github.com/RosettaCommons/RFdiffusion/blob/e22092420281c644b928e64d490044dfca4f9175/rfdiffusion/inference/model_runners.py#L362

Which breaks my code from a couple of months ago:

python /mnt/scratch/RFdiffusion/scripts/run_inference.py inference.ckpt_override_path=/mnt/scratch/RFdiffusion/models/Base_epoch8_ckpt.pt inference.output_prefix=fragment_designs/6WMP_DNA_fragments_design inference.input_pdb=6WMP_DNA_fragments.pdb inference.num_designs=10 contigmap.contigs=[13-23/A1-18/1-10/B1-18/5-15]

Could you please explain the change and the alternative? As I understand it I should now just keep A and B in the same chain? Part of the use-case for me was to merge different chains...