weather/noaa: Improve the days shown in the forecast

Reason for the change

Previously, a day would be filtered out from showing in the applet when it didn't have for instance the minimum temperature (which usually happens for the last day)

Let's filter out day forecasts only if they don't provide the weather condition, instead of min/max temperatures.

Also report the actual number of days after the filtering, instead of the total days in the report. Otherwise we could show less days than we claim on the tab.

Test plan

On the weather applet select a location with the NOAA provider. In some cases it could show "8 days" but only 7 are shown.

Not dependent, but might work better together with !4355 (merged)

Screenshots or screen recordings

Before	After