[BUG]: MOT exporting should not adjust dataset timesteps
### Description of the bug

Given that a[ preprocessing function ](https://github.com/twosixlabs/armory/blob/f529d887e95725bb730c11c5810a68dbe117cc11/armory/data/adversarial_datasets.py#L1019)was added to the MOT dataset loader to 0-index the timesteps, the exporting code no longer needs to [adjust](https://github.com/twosixlabs/armory/blob/f529d887e95725bb730c11c5810a68dbe117cc11/armory/instrument/export.py#L331-L336) for 1-indexed timesteps.

### Steps To Reproduce

Run any MOT config (that doesn't use coco format data) with "export_batches":true; you should see a key error because the timestep indices are off by one

### Additional Information

_No response_
diff --git a/armory/instrument/export.py b/armory/instrument/export.py
index f5f131ae..44172572 100644
--- a/armory/instrument/export.py
+++ b/armory/instrument/export.py
@@ -327,13 +327,11 @@ class VideoTrackingExporter(VideoClassificationExporter):
 
         if y.ndim == 1:
             y = np.expand_dims(y, 0)
-        y_dict = {
-            int(timestep - 1): [] for timestep in set(y[:, 0])
-        }  # 0-index timesteps
+        y_dict = {int(timestep): [] for timestep in set(y[:, 0])}
 
         for pred in y:
             # TODO filter out boxes with low confidence?
-            timestep = int(pred[0] - 1)
+            timestep = int(pred[0])
             x0, y0 = pred[2], pred[3]
             x1, y1 = pred[2] + pred[4], pred[3] + pred[5]
             y_dict[timestep].append([x0, y0, x1, y1])
['armory/instrument/export.py']