wallet: Recompute wallet TXOs after descriptor migration

When a legacy wallet has been migrated to contain descriptors, but
before the transactions have been updated to match, we need to recompute
the wallet TXOs so that the transaction update will work correctly.

src/wallet/wallet.cpp

@@ -3901,6 +3901,10 @@ util::Result<void> CWallet::ApplyMigrationData(WalletBatch& local_wallet_batch,
         return util::Error{_("Error: Unable to read wallet's best block locator record")};
     }
 
+    // Update m_txos to match the descriptors remaining in this wallet
+    m_txos.clear();
+    RefreshAllTXOs();
+
     // Check if the transactions in the wallet are still ours. Either they belong here, or they belong in the watchonly wallet.
     // We need to go through these in the tx insertion order so that lookups to spends works.
     std::vector<Txid> txids_to_delete;