message: Update to use short TOC titles
  Given most of the tutorials uses short TOC titles (like `BigQuery`,
  `Prometheus metrics`), this PR proposes to stay with short TOC titles
  for all entries to make it consistent, and make appearance aligned in the page.
diff: toc:
  - title: "BigQuery"
  path: /io/tutorials/bigquery
  -- title: "Decode DICOM files for medical imaging"
  +- title: "Decode DICOM files"
  path: /io/tutorials/dicom
  -- title: "Azure blob storage with TensorFlow"
  +- title: "Azure blob storage"
  path: /io/tutorials/azure
  - title: "Prometheus metrics"
  path: /io/tutorials/prometheus
  