Update javaxval/src/test/java/org/baeldung/javaxval/messageinterpolator/ParameterMessageInterpolaterIntegrationTest.java

update to use the givenX_whenY_thenZ naming convention for tests

Co-Authored-By: KevinGilmore <kpg102@gmail.com>

mapstruct/src/main/java/com/baeldung/entity/Customer.java

@@ -0,0 +1,25 @@
+package com.baeldung.entity;
+
+public class Customer {
+
+    private String firstName;
+    private String lastName;
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public Customer setFirstName(String firstName) {
+        this.firstName = firstName;
+        return this;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public Customer setLastName(String lastName) {
+        this.lastName = lastName;
+        return this;
+    }
+}