Do not suggest "convert to object" for sealed sub-classes with state

So #KT-24816 Fixed

idea/testData/inspectionsLocal/convertSealedSubClassToObject/ownState.kt

@@ -0,0 +1,8 @@
+// PROBLEM: none
+// WITH_RUNTIME
+
+sealed class SC {
+    <caret>class U : SC() {
+        val a = mutableListOf<String>()
+    }
+}