fix: array reference being reused (#22480)

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## **Description**

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There was a `transactions` array reference that was being reused on
every run of the selector, so duplicate items were being added and
breaking the transactions view.

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CHANGELOG entry: Fixed issue with activity list showing blank spaces

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/ASSETS-1751

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Author: bergarces

app/selectors/multichain/multichain.ts

@@ -521,7 +521,9 @@ export const selectNonEvmTransactionsForSelectedAccountGroup =
       }
 
       const aggregated = {
-        ...DEFAULT_TRANSACTION_STATE_ENTRY,
+        transactions: [],
+        next: null,
+        lastUpdated: 0,
       } as NonEvmTransactionStateEntry;
 
       for (const account of selectedGroupAccounts) {