After 6.2.2 - notification popups are centered on wrong monitor

[dpazdan]

Describe the bug
If a person uses multiple monitors, their popup notifications could display centered on a screen they are not using MetaMask on.

To Reproduce
Steps to reproduce the behavior:
On a Multiple monitor setups.
Running 6.2.2 w/ #6271: Center all notification popups

Expected behavior
It should always center or display on the same screen the user is focused on.