VZD | Update ETL to add `atd_mode_category_metadata` value on crash record creation or update

[atdservicebot]

• Update the atd-etl code so that when a new crash is inserted or or an existing one changes in CRIS, we can parse the related Unit records and insert a JSON value for `atd_mode_category_metadata

  • Schema Example:

  {
  "units": [
    {
      "unit_id": 1,
      "unit_mode_category_id": 1,  // "Passenger car" via lookup
      "unit_fatalities": 0, 
      "unit_injuries": 0
    },
    {
      "unit_id": 2,
      "unit_mode_category_id": 5,  // "Bicycle" via lookup
      "unit_fatalities": 1,
      "unit_injuries": 0
    },
  ]
  }

Migrated from atd-vz-data #633