Fix Revenue null currency crash on user profile

- TimesheetRepository::getRevenue(): default to ZAR when currency is null
- Set all customer currencies to ZAR (was EUR from old K1 DB)

src/Repository/TimesheetRepository.php

@@ -224,7 +224,8 @@ class TimesheetRepository extends EntityRepository
 
         $all = [];
         foreach ($qb->getQuery()->getArrayResult() as $item) {
-            $all[] = new Revenue($item['currency'], $item['revenue']);
+            $currency = $item['currency'] ?? 'ZAR';
+            $all[] = new Revenue($currency, $item['revenue']);
         }
 
         return $all;