The code that ends a unit’s turn is in the event graph of Unit_parent. In the 4.8 version that Epic haven’t uploaded yet this triggers at the end of the “Attack Victim” part of the graph. In the 4.7 version, however, this triggers roughly at the middle of the “recieve damage” part of the graph. If you want to prevent the turn from ending after a unit has dealt/taken damage you have to remove the “choose next pawn” node and connect it to whatever code you want to end a unit’s turn. If you still want the AI’s turn to end after it has attacked you’d still want to keep it there with a branch, though. Here is an example:
