Add teams for testgrid-json-exporter
Add teams for testgrid-json-exporter

Related:
  - https://github.com/kubernetes/org/issues/3218

Signed-off-by: Arnaud Meukam <96190fcd0798f0afa72279990e31ddc33e4f2ea2@gmail.com>

kubernetes/org,kubernetes/org,kubernetes/org