[Test] Move KotlinAgainstKotlin tests under BlackBoxCodegen tests

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

@@ -0,0 +1,17 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND: NATIVE
+// MODULE: lib
+// FILE: A.kt
+
+package a
+
+class Box() {
+    internal fun result(value: String = "OK"): String = value
+}
+
+// MODULE: main(lib)
+// FILE: B.kt
+
+fun box(): String {
+    return a.Box().result()
+}