[Test] Move KotlinAgainstKotlin tests under BlackBoxCodegen tests

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

@@ -0,0 +1,17 @@
+// MODULE: lib
+// FILE: A.kt
+
+package aaa
+
+fun hello() = 17
+
+// MODULE: main(lib)
+// FILE: B.kt
+
+fun box(): String {
+    val h = aaa.hello()
+    if (h != 17) {
+        throw Exception()
+    }
+    return "OK"
+}