Update `testgrid/config.yaml` with periodic-features-no-freeze
Update `testgrid/config.yaml` with periodic-features-no-freeze

Signed-off-by: Stephen Augustus <0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33@agst.us>

GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid