HAsmartirrigation: [Bug] Error adding entities for domain sensor with platform smart_irrigation

Describe the bug Upon HA start-up I get the following error:

2023-07-12 03:33:37.271 ERROR (MainThread) [homeassistant.components.sensor] Error adding entities for domain sensor with platform smart_irrigation
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 504, in async_add_entities
    await asyncio.gather(*tasks)
  File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 788, in _async_add_entity
    await entity.add_to_platform_finish()
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 1006, in add_to_platform_finish
    self.async_write_ha_state()
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 742, in async_write_ha_state
    self._async_write_ha_state()
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 810, in _async_write_ha_state
    state = self._stringify_state(available)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 748, in _stringify_state
    if (state := self.state) is None:
                 ^^^^^^^^^^
  File "/config/custom_components/smart_irrigation/sensor.py", line 557, in state
    self._state = self.update_state()
                  ^^^^^^^^^^^^^^^^^^^
  File "/config/custom_components/smart_irrigation/sensor.py", line 516, in update_state
    self.evapotranspiration = self.get_evapotranspiration(data)
                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/config/custom_components/smart_irrigation/sensor.py", line 694, in get_evapotranspiration
    t_dew = float(data["dew_point"])
                  ~~~~^^^^^^^^^^^^^
KeyError: 'dew_point'

To Reproduce Steps to reproduce the behavior:

1. Upon Home Assistant startup
2. See error

Expected behavior A clear and concise description of what you expected to happen.

My configuration Using in sensors-only mode, no OWM:

{
  "version": 1,
  "domain": "smart_irrigation",
  "title": "Smart Irrigation",
  "data": {
    "number_of_sprinklers": 6.0,
    "flow": 12.0,
    "area": 135.0,
    "api_key": null,
    "reference_evapotranspiration": [
      0.2,
      0.2,
      2.2,
      2.2,
      2.2,
      3.9,
      5.4,
      3.5,
      0.2,
      0.2,
      0.2,
      0.2
    ],
    "name": "Smart Irrigation",
    "sources": {
      "use_owm_precipitation": false,
      "use_owm_temperature": false,
      "use_owm_min_temperature": false,
      "use_owm_max_temperature": false,
      "use_owm_dewpoint": false,
      "use_owm_pressure": false,
      "use_owm_humidity": false,
      "use_owm_windspeed": false,
      "calculate_solar_radiation": false,
      "calculate_ET_value": true
    },
    "sensors": {
      "sensor_precipitation": "sensor.icorun3_precipitation_today",
      "sensor_temperature": "sensor.weather_outside_temperature",
      "sensor_min_temperature": "sensor.aggregation_temperature_daily_outside_min",
      "sensor_max_temperature": "sensor.aggregation_temperature_daily_outside_max",
      "sensor_dewpoint": "sensor.icorun3_dewpoint",
      "sensor_pressure": "sensor.icorun3_pressure",
      "sensor_humidity": "sensor.weather_outside_humidity",
      "sensor_windspeed": "sensor.icorun3_wind_speed",
      "sensor_solar_radiation": "sensor.icorun3_solar_radiation"
    }
  },
  "options": {},
  "pref_disable_new_entities": false,
  "pref_disable_polling": false,
  "source": "user",
  "unique_id": "Smart Irrigation",
  "disabled_by": null
}

Installed version 0.0.79