Pins should change color based on recent status reports

[sgammon]

Description

Based on the most recent reports submitted on the app, the pins for each hospital should change color. As pressure on a given facility increases, it should reflect the current state of that pressure on the map.

For instance, the map should depict a blue/regular color dot when no pressure is experienced at a healthcare facility, and perhaps orange or red if high pressure is experienced at the facility (with varying shades in between to indicate degree).

Part of #7.

[sgammon]

Link to subfeature: https://covidmap.productboard.com/feature-board/planning/features/4238279