Add job / toolchain / runtime fields to the (some?) json exporters

The corresponding columns are already present for most (not sure about xml) other exporter types, but only present in the json files as part of the DisplayInfo:

> "DisplayInfo":"QuantityFromUnit.new(value,unit): Job-MRXVVK(Runtime=.NET 5.0, Toolchain=netcoreapp50, IterationCount=3, LaunchCount=1, WarmupCount=3)

I'm not sure if they should be added to all json exporters, but I think it would be great if at least fulljson would have them.