Add a config for BigSmall

[tphlru]

Please add a configuration file (./configs/infer_configs) for BigSmall pre-trained models (https://github.com/ubicomplab/rPPG-Toolbox/blob/main/final_model_release/BP4D_BigSmall_Multitask_Fold3.pth)

If it's possible for a multi-model. If there are problems with this, could you please give some guidelines for using BigSmall's pre-trained models.

[girishvn]

Hi @tphlru,

I will add this to my TODOs for things to update.
For the time-being please refer to the train config for BigSmall. It should be fairly straightforward to adapt the config for inference.

You can refer to other inference configs - essentially the TOOLBOX_MODE should be set to "only_test" and the desired MODEL_PATH should be specified.