device_class and state_class needed for termostato_<name>_temperature and humidity

[ynlng]

The integration's Temperature and Humidity mqtt sensors need to have device_class and state_class set. These attributes will make them suitable for inclusion in graphs.

- name: termostato_1_humidity
  state_topic: /bticino/xx/status
  value_template: '{{ value_json.humidity|int }}'
  unit_of_measurement: '%'
  icon: mdi:water-percent
  device_class: humidity
  state_class: measurement


- name: termostato_1_temperature
  state_topic: /bticino/xx/status
  value_template: '{{ value_json.temperature }}'
  unit_of_measurement: '°C'
  icon: mdi:thermometer
  device_class: temperature
  state_class: measurement