Add predictions of LoS (i.e. d/c within 48h) to sitrep

[docsteveharris]

• how to join onto patients

URL is
http://uclvlddpragae08:5007/predictions/icu/discharge?ward=T03
but data is

{
  "data": [
    {
      "prediction_id": 123275,
      "episode_slice_id": 228457,
      "model_name": "bournville_rf",
      "model_version": 3,
      "prediction_as_real": 0.7405744713405086,
      "predict_dt": "2022-01-04T23:02:56.919547+00:00"
    },
    {