Add video decoding to LeRobotDataset (#92)

tests/data/lerobot/aloha_sim_transfer_cube_scripted/meta_data/info.json

@@ -1,3 +1,4 @@
 {
-    "fps": 50
+    "fps": 50,
+    "video": 1
 }

tests/data/lerobot/aloha_sim_transfer_cube_scripted/train/dataset_info.json

@@ -3,7 +3,7 @@
   "description": "",
   "features": {
     "observation.images.top": {
-      "_type": "Image"
+      "_type": "VideoFrame"
     },
     "observation.state": {
       "feature": {

tests/data/lerobot/aloha_sim_transfer_cube_scripted/train/state.json

@@ -4,10 +4,10 @@
       "filename": "data-00000-of-00001.arrow"
     }
   ],
-  "_fingerprint": "e4d7ad2b360db1af",
+  "_fingerprint": "eb759bbf60df7be9",
   "_format_columns": null,
   "_format_kwargs": {},
-  "_format_type": "torch",
+  "_format_type": null,
   "_output_all_columns": false,
   "_split": null
 }