Collect the icon tint from the StateFlow

The previous code only picked the initial tint value and wouldn't get updated

Test: manually on demo mode
Fixes: 402605944
Flag: com.android.settingslib.flags.new_status_bar_icons
Flag: com.android.systemui.status_bar_root_modernization
Change-Id: I6e5eaa39d3ebf527e026f1d15bd0b906ffb581fe