Fix validation build to work with new build agents (#11054)

tests/screenshots

@@ -1 +1 @@
-Subproject commit 7ed61694f4c86c0fc7e206514d6953a096aba43f
+Subproject commit 281080325087d3059339e6c3d718544d278d3bdd

uitest/src/main/java/com/vaadin/tests/util/TestDataGenerator.java

@@ -95,6 +95,9 @@ public class TestDataGenerator {
         c.set(Calendar.YEAR, r.nextInt(100) + 1900);
         c.set(Calendar.MONTH, r.nextInt(12));
         c.set(Calendar.DAY_OF_MONTH, r.nextInt(31));
+        c.set(Calendar.HOUR_OF_DAY, 11);
+        c.set(Calendar.HOUR, 11);
+        c.set(Calendar.AM_PM, Calendar.AM);
 
         return c.getTime();
     }