Make sure the filtered hourprices get updated every hour.

[Roeland54]

should fix #186

[Pluimvee]

There shouldnt be made an update requestfrom the sensor to the coordinator as:

1. this update request is now triggered for each sensor, with corresponding update and refilter logic
2. the DataUpdateCoordinator has its own refresh event from HA

See the DataCoordinator construct

[Roeland54]

It is needed because the dict of filtered values that are used for calculations need to be updated on the hour mark. But I agree it only should be done once and not for each sensor. The coordinator update to fetch the data is ran with an interval of 60 min but not exacty on the hour. Mostly depends on the startup time of HA or when the integration is reloaded. Feel free to open a PR If you feel you can improve something.