fix(en): Initialize SyncState in OutputHandler (#2618)

## What ❔

OutputHandler must be added after ExternalIO, because the latter is
adding SyncStateResource

## Why ❔

Bug

## Checklist

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- [ ] PR title corresponds to the body of PR (we generate changelog
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core/bin/external_node/src/node_builder.rs

@@ -216,8 +216,8 @@ impl ExternalNodeBuilder {
             rocksdb_options,
         );
         self.node
-            .add_layer(persistence_layer)
             .add_layer(io_layer)
+            .add_layer(persistence_layer)
             .add_layer(main_node_batch_executor_builder_layer)
             .add_layer(state_keeper_layer);
         Ok(self)