[sat] add config for the opportunistic satellite icon

This config allows for turning off the behavior of the opportunistic
satellite icon. That is, the icon that shows when all connections are
out of service and satellite is provisioned and allowed.

Test: DeviceBasedSatelliteViewModelTest
Test: all other mobile tests
Bug: 376310933
Flag: EXEMPT bugfix
Change-Id: I81e00048ab4a87c68f0ec9fb6f12115656e9ec77