Front-end: Examine Select-all Behavior in FacilitiesMultiSelect.js

[decause-gov]

Issue Report

Front-end: Examine Select-all Behavior in FacilitiesMultiSelect.js

Expected behavior

Behavior could be as expected, but worth examining for possible performance improvements.

Actual behavior

src/components/FacilitiesMultiSelect.js

1. Inside the useEffect, you are checking the length of facilities against the length of
   selected facilities to determine if "Select All" should be on or off. In this case, the
   selectedFacilities dependency could potentially cause frequent re-renders.

2. The code block: selectedFacilities.indexOf(id) > -1 inside the map function
   can be performance-intensive if there are many facilities since indexOf would be O(n).

3. The "Select All" option toggles the state, which means if all facilities are already selected
   and a user clicks "Select All" again, it will deselect all. If this is the desired behavior, it's
   okay. If not, you might want to address it.