Fix: Add a delimited file (CSV) to the map

[yulinscottkang]

Fixes https://samples.azuremaps.com/spatial-io-module/add-a-delimited-file-(csv)-to-the-map

Maplibre has a known issue when displaying a large number of points that are close to each other.

Fixed by limiting the number of features to be shown.

[rbrundritt]

Let's hold off on merging this one. This limitation never existed in the first 8 years of Azure Maps. There must have been a breaking change in MapLibre that will need to be investigated and fixed. I've rendered hundreds of thousands on points on the map for years without any issues or errors.