Alert Polygon intersection coverage precision

[thenav56]

Currently, alerts are tagged using alert-info polygons by checking the intersection with admin1 geo data.
The intersection returns all geoarea touched by the polygon. For polygon which represents a geoarea will also tag all geoarea surrounded by the geoarea.

alert-hub-backend/apps/cap_feed/formats/cap_xml.py

Lines 190 to 193 in 29d5c29

	possible_admin1s = Admin1.objects.filter(
	country=alert.country,
	# TODO: Check for performance issues
	geometry__intersects=polygon,

We may need to optimize to select the required geoareas only.

NOTE: geoarea -> admin1 geoarea