Keep API results the same as before

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

lib/Db/Board.php

@@ -63,6 +63,10 @@ class Board extends RelationalEntity {
 		if ($this->shared === -1) {
 			unset($json['shared']);
 		}
+		// FIXME: Ideally the API responses should follow the internal data structure and return null if the labels/acls have not been fetched from the db
+		// however this would be a breaking change for consumers of the API
+		$json['acl'] = $this->acl ?? [];
+		$json['labels'] = $this->labels ?? [];
 		return $json;
 	}