[FEATURE] make rootPath from virtualFolders available inside launch.json

[yawhide]

Is your feature request related to a problem? Please describe.
I am using virtualFolders in my settings.json and running tests works great! thanks for that feature!

however, debugging tests is awkward. I have to create a launch.json for each item in my virtualFolders array and hardcode a config path to match the rootPath in each virtualFolder defined.

Describe the solution you'd like
Could we make rootPath available to use inside launch.json? This way, i could set "cwd": "${jest.[name].rootPath}" or something similar? this would save me from having to hardcode the full path to the virtualFolder's jest file.

If we could do something like ${jest.[name].rootPath}, then could we only have to have 1 launch.json and it would support all virtualFolders?

Describe alternatives you've considered
n/a

Additional context
n/a