[Test] Move KotlinAgainstKotlin tests under BlackBoxCodegen tests

compiler/testData/codegen/box/compileKotlinAgainstKotlin/simpleValAnonymousObject.kt

@@ -0,0 +1,22 @@
+// MODULE: lib
+// FILE: A.kt
+
+package pkg
+
+interface ClassA {
+    companion object {
+        val DEFAULT = object : ClassA {
+            override fun toString() = "OK"
+        }
+    }
+}
+
+// MODULE: main(lib)
+// FILE: B.kt
+
+import pkg.ClassA
+
+fun box(): String {
+    val obj = ClassA.DEFAULT
+    return obj.toString()
+}