Include resources on maps only when the geocoding got valid coords

[leio10]

🎩 What? Why?

For in-person meetings, it is not allowed to leave the address field empty, or with a value that can't be located in the geocoding service database. But online meetings allow admins to leave it empty, and in that case the geocoding library stores NaN for the longitude and latitude fields. As these values are not nil or false, the geocoded? method returns true, even when those values are not valid. This results in the meetings map to raise a JS error and to appear completely empty, as explained in #7983.

This PR adds a new method geocoded_and_valid? that is used to avoid trying to paint the online meetings on the map. I didn't override the geocoded? method because it could be used by the library to try to geocode the meeting again if it returns false.

📌 Related Issues

• Fixes Meeting map does not show meetings when there are online and in-person meetings #7983

Testing

1. Configure the maps service for Decidim
2. Add an in-person meeting and an online meeting to a meetings component
3. Go to the meetings component front page and check that the map shows the in-person meeting properly