feat: configure end to end test prover cache pool size

Author: jpraynaud

mithril-test-lab/mithril-end-to-end/src/mithril/aggregator.rs

@@ -85,6 +85,7 @@ impl Aggregator {
                 aggregator_config.cardano_node_version,
             ),
             ("CHAIN_OBSERVER_TYPE", aggregator_config.chain_observer_type),
+            ("CARDANO_TRANSACTIONS_PROVER_CACHE_POOL_SIZE", "5"),
         ]);
         let args = vec![
             "--db-directory",