enh: add notebook demonstrating access to data from Imaging Data Commons (#2063)

### Description
This notebook demonstrates how to load images and segmentations from
[Imaging Data
Commons](https://portal.imaging.datacommons.cancer.gov/explore/).

### Checks
<!--- Put an `x` in all the boxes that apply, and remove the not
applicable items -->
- [x] Avoid including large-size files in the PR.
- [x] Clean up long text outputs from code cells in the notebook.
- [x] For security purposes, please check the contents and remove any
sensitive info such as user names and private key.
- [x] 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
- [x] Notebook runs automatically `./runner.sh -t <path to .ipynb file>`


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Documentation**
* Added a tutorial notebook showing how to query/download IDC cancer
imaging data and load DICOM images and segmentations into MONAI; removed
a stray non‑ASCII line in the docs.
* **Chores**
* Updated CI rules to skip executing the new tutorial notebook during
automated runs to avoid long or incompatible executions.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

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Signed-off-by: Andrey Fedorov <andrey.fedorov@gmail.com>
Signed-off-by: Andrey Fedorov <fedorov@bwh.harvard.edu>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Eric Kerfoot <17726042+ericspod@users.noreply.github.com>