[K/N][Tests] Adjust moved codegen tests to new infra

^KT-61259

native/native.tests/testData/codegen/function/defaultsWithVarArg2.kt

@@ -3,15 +3,23 @@
  * that can be found in the LICENSE file.
  */
 
-package codegen.function.defaultsWithVarArg2
-
 import kotlin.test.*
 
+val sb = StringBuilder()
+
 fun foo(vararg arr: Int = intArrayOf(1, 2)) {
-    arr.forEach { println(it) }
+    arr.forEach { sb.appendLine(it) }
 }
 
-@Test fun runTest() {
+fun box(): String {
     foo()
     foo(42)
+
+    assertEquals("""
+        1
+        2
+        42
+
+    """.trimIndent(), sb.toString())
+    return "OK"
 }