fix: quiqqer/erp#100

(cherry picked from commit 38771499)

Co-authored-by: Henning Leutz <leutz@pcsg.de>

src/QUI/ERP/Accounting/Calc.php

@@ -535,6 +535,8 @@ public function calcArticlePrice(Article $Article, $callback = false)
         }
 
         $nettoPrice = $Article->getUnitPriceUnRounded()->value();
+        $nettoPrice = round($nettoPrice, $Currency->getPrecision());
+
         $vat = $Article->getVat();
         $basisNettoPrice = $nettoPrice;
         $nettoSubSum = $this->round($nettoPrice * $Article->getQuantity());