Cannot access child value on Newtonsoft.Json.Linq.JProperty.

[djnicholson]

If a launch.json entry has a storage key but it is not of the expected type the user sees the following error in VS Code:

Cannot access child value on Newtonsoft.Json.Linq.JProperty.

It would be better to tell them what is wrong with their launch config (or maybe just ignore the malformed storage element).