Move java8 'compileKotlinAgainstKotlin' test under 'codegen/java8/compileKotlinAgainstKotlin/jvm6' folder

compiler/testData/codegen/java8/compileKotlinAgainstKotlin/jvm6/jdk8Against6.kt

@@ -0,0 +1,21 @@
+// FILE: A.kt
+import java.util.*
+class Jdk6List<F> : AbstractList<F>() {
+    override fun get(index: Int): F {
+        return "OK" as F
+    }
+
+    override val size: Int
+        get() = 2
+
+}
+
+// FILE: B.kt
+// FULL_JDK
+
+fun box(): String {
+    val result = Jdk6List<String>().stream().filter { it == "OK" }.count()
+    if (result != 2L) return "fai1: $result"
+
+    return "OK"
+}