Multi Wan Failover, Add Stability Setting for Fail-Back

[tracerrx]

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Is your feature request related to a problem? Please describe.

In multi WAN environments with failover enabled, when the primary WAN is unstable and the secondary WAN is stable, be sticky to the stable WAN so default WAN does not bounce back and forth.

Describe the solution you like

Add an option to either gateway monitoring or gateway groups to require X minutes of stability of Primary wan before failing back.

Describe alternatives you considered

Additional context

Add any other context or screenshots about the feature request here or links to relevant forum thread or similar