Ensure US number format in tests ('.' is decimal point)

de.hftstuttgart.cityunits.tests/src/de/hftstuttgart/cityunits/tests/QuantityTest.java

 package de.hftstuttgart.cityunits.tests;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.Locale;
+import java.util.Locale.Category;
+
 import javax.measure.Quantity;
 import javax.measure.Unit;
 import javax.measure.quantity.Area;
@@ -19,6 +23,8 @@ class QuantityTest
 	static void init() {
 		// Initialize additional units like metric ton, $ and € with their labels
 		UrbanSimulationUnits.getInstance();
+		// Ensure US number format (interpret '.' as decimal point)
+		Locale.setDefault(Category.FORMAT, Locale.US);
 	}
 
 	@Test
@@ -57,7 +63,7 @@ class QuantityTest
 	void testkWhPerCubicMeter() {
 		Quantity<?> q = Quantities.getQuantity((String)"5.2 kW*h/m³");
 		assertEquals("[M]/([L]·[T]²)", q.getUnit().getDimension().toString(), "Wrong dimension!");
-		assertEquals("187200000 W·s/m³", q.toSystemUnit().toString());
+		assertEquals("18720000 W·s/m³", q.toSystemUnit().toString());
 	}
 
 }