Fix omniverse tutorial missing lib error (#1955)

Fixes #1954

### Description


### Checks
<!--- Put an `x` in all the boxes that apply, and remove the not
applicable items -->
- [ ] Avoid including large-size files in the PR.
- [ ] Clean up long text outputs from code cells in the notebook.
- [ ] For security purposes, please check the contents and remove any
sensitive info such as user names and private key.
- [ ] Ensure (1) hyperlinks and markdown anchors are working (2) use
relative paths for tutorial repo files (3) put figure and graphs in the
`./figure` folder
- [ ] Notebook runs automatically `./runner.sh -t <path to .ipynb file>`

Signed-off-by: Yiheng Wang <vennw@nvidia.com>

Author: yiheng-wang-nv

modules/omniverse/omniverse_integration.ipynb

@@ -57,6 +57,7 @@
    "outputs": [],
    "source": [
     "!python -c \"import monai\" || pip install -q \"monai-weekly[nibabel]\"\n",
+    "!python -c \"import skimage\" || pip install -q scikit-image\n",
     "!python -c \"import vtk\" || pip install -q vtk\n",
     "!python -c \"import pxr\" || pip install -q usd-core\n",
     "!python -c \"import trimesh\" || pip install -q trimesh\n",
@@ -466,6 +467,11 @@
     "    print(f\"Saved whole segmentation {all_organ_filename}\")\n",
     "\n",
     "\n",
+    "# if workflow.run() is uncommented and run, an image and a label files will be generated in the output folder\n",
+    "# for example, file paths are like this:\n",
+    "# f\"{bundle_root}/output/sample_20250317_065034_415537_image.nii.gz\"\n",
+    "# f\"{bundle_root}/output/sample_20250317_065034_415537_label.nii.gz\"\n",
+    "# then you can replace the \"input_nii_path\" below with the generated label file\n",
     "input_nii_path = f\"{bundle_root}/datasets/IntegrationTest-AbdomenCT.nii.gz\"\n",
     "output_nii_path = f\"{bundle_root}/datasets/monai/nii\"\n",
     "output_obj_path = f\"{bundle_root}/datasets/monai/obj\"\n",