tests: Update external tests (1.1.2-dev-393)

backend.native/tests/external/codegen/box/classes/kt2480.kt

@@ -0,0 +1,13 @@
+fun box() = Class().printSome()
+
+public abstract class AbstractClass<T> {
+    public fun printSome() : T = some
+
+    public abstract val some: T
+}
+
+public class Class: AbstractClass<String>() {
+    public override val some: String
+        get() = "OK"
+
+}