Add test for enum class with inner classes

compiler/testData/loadJava/compiledKotlin/enum/enumWithInnerClasses.kt

@@ -0,0 +1,16 @@
+//ALLOW_AST_ACCESS
+package test
+
+enum class Enum {
+    ENTRY1 ENTRY2
+
+    inner class Inner
+
+    class Nested
+
+    trait Trait
+
+    val c: Int = 1
+
+    fun f(): Int = 2
+}