Cleans up launch.json

[sanjeetsuhag]

This PR cleans up the launch.json that was polluted in #10824. The file is reverted back to what it was before the merge. The one change is changing the Chrome task from "pwa-chrome" to "chrome" as recommended by VS Code.

[cesium-concierge]

Thanks for the pull request @sanjeetsuhag!

• ✔️ Signed CLA found.
• ❔ CHANGES.md was not updated.
  • If this change updates the public API in any way, please add a bullet point to CHANGES.md.
• ❔ Unit tests were not updated.
  • Make sure you've updated tests to reflect your changes, added tests for any new code, and ran the code coverage tool.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.

[ggetz]

Thanks @sanjeetsuhag!