Merge boxWithStdlib testData into box, delete BoxWithStdlib test

compiler/testData/codegen/box/reflection/properties/publicClassValAccessible.kt

@@ -0,0 +1,14 @@
+// WITH_REFLECT
+
+import kotlin.reflect.jvm.accessible
+
+class Result {
+    public val value: String = "OK"
+}
+
+fun box(): String {
+    val p = Result::value
+    p.accessible = false
+    // setAccessible(false) should have no effect on the accessibility of a public reflection object
+    return p.get(Result())
+}