indexer: hotfix 0013_recreate_table_transactions

turns out, some transactions in stage were indexed twice (same hash but different ID),
this likely happened during last chain upgrade. handle this situation gracefully by
simply replacing the duplicate entries.

vochain/indexer/migrations/0013_recreate_table_transactions.sql

@@ -10,7 +10,7 @@ CREATE TABLE transactions_new (
 );
 
 -- Copy data from the old table to the new table
-INSERT INTO transactions_new (hash, block_height, block_index, type)
+INSERT OR REPLACE INTO transactions_new (hash, block_height, block_index, type)
 SELECT hash, block_height, block_index, type
 FROM transactions;