Home Assistant Long-term Statistics support

[robloh]

Thanks for making this component, it's been working great!

HASS 2021.8 introduced long-term statistics (see https://www.home-assistant.io/blog/2021/08/04/release-20218/) which would be nice to have support for with yahoofinance.

From what I can tell the only thing that should be needed is to set the "state_class" property to "measurement", see: https://developers.home-assistant.io/docs/core/entity/sensor/#long-term-statistics

After this change the long term statistics can be seen in the developer tools (https://my.home-assistant.io/redirect/developer_statistics/) or by using the statistics graph card (https://www.home-assistant.io/dashboards/statistics-graph/)

As a secondary enhancement it might be good idea to set "device_class" property to "monetary"? See: https://www.home-assistant.io/integrations/sensor/#device-class

[robloh]

This seems to work great, thank you!