How to bring reverting/in recovery secondary db back online after failover

Issue:

Secondary Database stuck in “Reverting/In Recovery” after Failover.

Resolution:

The only way to fix is by restarting the secondary machine, it then will kill the system process which was locking the master db. 

Sources:

https://learn.microsoft.com/en-us/answers/questions/138501/how-to-bring-reverting-in-recovery-secondary-db-ba