fix(vm): Save empty bootloader memory for batches with ancient vms (m…

…atter-labs#991)

## What ❔

Save empty data to the database if bootloader memory doesn't exists. 
It's possible for old vms

## Why ❔

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## Checklist

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- [ ] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [ ] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [ ] Code has been formatted via `zk fmt` and `zk lint`.
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- [ ] Linkcheck has been run via `zk linkcheck`.

Signed-off-by: Danil <[email protected]>

core/lib/zksync_core/src/state_keeper/io/seal_logic.rs

@@ -154,11 +154,15 @@ impl UpdatesManager {
             .final_execution_state
             .deduplicated_events_logs;
 
+        let final_bootloader_memory = finished_batch
+            .final_bootloader_memory
+            .clone()
+            .unwrap_or_default();
         transaction
             .blocks_dal()
             .insert_l1_batch(
                 &l1_batch,
-                finished_batch.final_bootloader_memory.as_ref().unwrap(),
+                &final_bootloader_memory,
                 self.pending_l1_gas_count(),
                 &events_queue,
                 &finished_batch.final_execution_state.storage_refunds,