Try to handle PendingRollbackError (#2319)

Try to handle PendingRollbackError

I think this could solve the PendingRollbackError issue, however I don't really have a way to test it. Once this is merged, I can try to rescale postgres on stage in order to hopefully trigger the error. What do you think?

Reviewed-by: Maja Massarini
Reviewed-by: Laura Barcziová
Reviewed-by: Nikola Forró