Objectnav datasets use `misc` category

[smorad]

🐛 Bug

The episodes generated for the mp3d objectnav task include the misc (40) item category. This likely hinders agent training, as misc is too vague for even a human to understand. Current/future datasets would probably benefit from exclusion of misc (40) semantic targets, as well as: objects (39), unlabeled (41), void (0), wall (1), floor(2).

Steps to Reproduce

Steps to reproduce the behavior:

cfg:

DATASET:
  TYPE: ObjectNav-v1
  SPLIT: val_mini
  DATA_PATH: "/root/habitat-lab/data/datasets/objectnav/mp3d/v1/{split}/{split}.json.gz"
  SCENES_DIR: "/root/habitat-lab/data/scene_datasets/"

code:

scene = self._env.sim.semantic_annotations()
label_to_str_cat = {
                int(obj.id.split("_")[-1]): obj.category.name()
                for obj in scene.objects
            }
print(label_to_str_cat[obs['objectgoal'][0]])

>>> "misc"