jvm-abi-gen: Add tests for uses of private Kotlin classes from Java

plugins/jvm-abi-gen/testData/compile/privateAnnotationsFromJavaLib/app/app.kt

@@ -0,0 +1,7 @@
+package app
+
+import lib.J
+
+fun runAppAndReturnOk(): String {
+    return if (J::class.java.annotations.size == 1) "OK" else "Fail"
+}

plugins/jvm-abi-gen/testData/compile/privateAnnotationsFromJavaLib/lib/J.java

@@ -0,0 +1,4 @@
+package lib;
+
+@A
+public class J {}

plugins/jvm-abi-gen/testData/compile/privateAnnotationsFromJavaLib/lib/lib.kt

@@ -0,0 +1,4 @@
+package lib
+
+@Retention(AnnotationRetention.RUNTIME)
+private annotation class A