Enhancements to JupyterLab and new icons

These enhancements were made to the JupyterLab environment:

• The Environment Explorer tab list view has been updated for a better user experience with narrow screens.
• New icons for the Healthcare Neurophysiology, Computer Vision, and Rapids conda environments in the Environment Explorer and Launcher tabs.
• The Launcher tab has been updated with:
  • A welcome section that provides getting started instructions.
  • Searching functionality.
  • A special section presenting the list of extensions provided by Oracle.