[wip] Use planet qa tiles instead of extracts

[geohacker]

This PR makes the workers use planet qa tile by default.

⚠️ It introduces a breaking change in countries.json for downstream consumers of that file including the osma-health front-end:

countries.json now looks like this:

{
  "botswana":{
      "bbox": [19.99865, -26.90597, 29.37530, -17.77814], // new
      "boundaries": { // new
        "type": "FeatureCollection",
        "features": [
          ......
        ]
      }
    }
}

This will take longer to run, but will be more accurate because tiles in the edges of the AOIs will no longer be skipped. There will still be a marginal overestimation because doing a full polygon membership per AOI is really expensive.

cc @smit1678 @kamicut @ascalamogna

[geohacker]

I just ran this for botswana and the total number of buildings jumped quiet high because there are bigger tiles outside of the boundary with very little overlap. This PR won't be ready until we can check whether each building belongs to the boundary of botswana, and hence is a bigger lift that what we have time for at this point.

We should stick to extracts for the time being until we finalise on the quality and feature requirements in the near future.