Make $repairSteps & $dispatcher mandatory

Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>

lib/private/Repair.php

@@ -76,7 +76,7 @@ class Repair implements IOutput {
 	 * @param IRepairStep[] $repairSteps array of RepairStep instances
 	 * @param EventDispatcherInterface $dispatcher
 	 */
-	public function __construct($repairSteps = [], EventDispatcherInterface $dispatcher = null) {
+	public function __construct(array $repairSteps, EventDispatcherInterface $dispatcher) {
 		$this->repairSteps = $repairSteps;
 		$this->dispatcher  = $dispatcher;
 	}