[KTLN-703] Kotlin Equivalent of Java's equalsIgnoreCase (#784)

* added unit tests

* fixed unit tests

* fixed unit tests

* fixed code

Author: albertache1998

core-kotlin-modules/core-kotlin-strings-4/src/test/kotlin/com/baeldung/equalsIgnoreCaseInKotlin/EqualsIgnoreCaseInKotlinUnitTest.kt

@@ -0,0 +1,35 @@
+package com.baeldung.equalsIgnoreCaseInKotlin
+
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+
+class EqualsIgnoreCaseInKotlinUnitTest {
+
+    @Test
+    fun `test string case insensitive comparison using equals and lowercase methods`() {
+         val result1 = "Hello".lowercase() == "hello".lowercase()
+         val result2 = "Hello".lowercase() == "world".lowercase()
+
+        assertTrue(result1)
+        assertFalse(result2)
+    }
+
+    @Test
+    fun `test string case insensitive comparison using equals methods`() {
+        val result1 = "Hello".equals("hello", true)
+        val result2 = "Hello".equals("world", true)
+
+        assertTrue(result1)
+        assertFalse(result2)
+    }
+
+    @Test
+    fun `test string case insensitive comparison using compareTo method`() {
+        val result1 = "Hello".compareTo("hello", true) == 0
+        val result2 = "Hello".compareTo("world", true) == 0
+
+        assertTrue(result1)
+        assertFalse(result2)
+    }
+}