Invalid w3c.json data

[dontcallmedom-bot]

The w3c.json file in this repo does not follow the expected data model. The following errors were detected:

• unknown group name: "tf/silver-tf"

_{This issue was detected and reported semi-automatically by validate-repos.}

[cwadamsoforacle]

@iadawn I think this one is for you.

[iadawn]

That should be fixed... although a bit unclear why it had been flagged.