perf: Make fetching user details lazy

Signed-off-by: Julius Härtl <jus@bitgrid.net>

lib/Service/CardService.php

@@ -119,7 +119,7 @@ class CardService {
 	public function enrichCards($cards) {
 		$user = $this->userManager->get($this->currentUser);
 
-		$cardIds = array_map(function (Card $card) {
+		$cardIds = array_map(function (Card $card) use ($user) {
 			// Everything done in here might be heavy as it is executed for every card
 			$cardId = $card->getId();
 			$this->cardMapper->mapOwner($card);