Update Nightlights data

New data is available on `s3://covid-eo-blackmarble`:

```
2021-02-10 22:16:54 1912121581 COVID_Dashboard_BMHD_Jan2020_Jan2021.tar.gz
2021-02-10 21:59:39 15118758242 COVID_Dashboard_VNP46A2_Jan2020_Jan2021.tar.gz
```

The issue around missing data that is mentioned in #535 should be solved with this update.