KT-4107 Don't generate readResolve for data objects

compiler/testData/codegen/box/dataObjects/serialization.kt

@@ -6,6 +6,7 @@
 // FIR_IDENTICAL
 
 import java.io.*
+import kotlin.test.*
 
 data object NonSerializableDataObject
 
@@ -14,7 +15,11 @@ data object SerializableDataObject: Serializable
 fun box(): String {
     ByteArrayOutputStream().use { baos ->
         ObjectOutputStream(baos).use { oos -> oos.writeObject(SerializableDataObject) }
-        ByteArrayInputStream(baos.toByteArray()).use { bais -> assert(java.io.ObjectInputStream(bais).readObject() === SerializableDataObject) }
+        ByteArrayInputStream(baos.toByteArray()).use { bais ->
+            val deseialized = ObjectInputStream(bais).readObject()
+            assertEquals(SerializableDataObject, deseialized)
+            assertNotSame(deseialized, SerializableDataObject)
+        }
     }
     return "OK"
 }

compiler/testData/codegen/box/dataObjects/serialization.txt

@@ -17,7 +17,6 @@ public final class SerializableDataObject {
     private method <init>(): void
     public method equals(@org.jetbrains.annotations.Nullable p0: java.lang.Object): boolean
     public method hashCode(): int
-    private final method readResolve(): java.lang.Object
     public @org.jetbrains.annotations.NotNull method toString(): java.lang.String
 }