Adjust the unit test (#6543)

* Add the code for article "Kotlin Annotations" (BAEL-2579)

* Adjust the Validation test

core-kotlin-2/src/test/kotlin/com/baeldung/annotations/ValidationTest.kt

@@ -0,0 +1,41 @@
+package com.baeldung.annotations
+
+import org.junit.Test
+import kotlin.test.assertTrue
+import kotlin.test.assertFalse
+
+class ValidationUnitTest {
+
+    @Test
+    fun whenAmountIsOneAndNameIsAlice_thenTrue() {
+        assertTrue(Validator().isValid(Item(1f, "Alice")))
+    }
+
+    @Test
+    fun whenAmountIsOneAndNameIsBob_thenTrue() {
+        assertTrue(Validator().isValid(Item(1f, "Bob")))
+    }
+
+
+    @Test
+    fun whenAmountIsMinusOneAndNameIsAlice_thenFalse() {
+        assertFalse(Validator().isValid(Item(-1f, "Alice")))
+    }
+
+    @Test
+    fun whenAmountIsMinusOneAndNameIsBob_thenFalse() {
+        assertFalse(Validator().isValid(Item(-1f, "Bob")))
+    }
+
+    @Test
+    fun whenAmountIsOneAndNameIsTom_thenFalse() {
+        assertFalse(Validator().isValid(Item(1f, "Tom")))
+    }
+
+    @Test
+    fun whenAmountIsMinusOneAndNameIsTom_thenFalse() {
+        assertFalse(Validator().isValid(Item(-1f, "Tom")))
+    }
+
+
+}