Use SQLite transactions when inserting `Cardano Transactions` and `Block Range Roots`

[jpraynaud]

Why

We can have a better insertion throughput if we use transactions in SQLite (see https://stackoverflow.com/questions/1711631/improve-insert-per-second-performance-of-sqlite). This can be used to accelerate the insertion on Cardano transactions and block range roots on the signer and aggregator.

What

Create insert queries inside a transaction when importing the Cardano Transactions and block range roots.

How

• [x] Create a benchmark for current implementation
• [x] Add SQLite transactions when importing Cardano Transactions and block range roots
• [x] Measure the performance optimization between the two versions

After

• Assess the relevance of adding SQLite transactions when importing block range roots
• How can we deploy this optimizations on the other store of signer/aggregator (do we need to pool connections to database?)