add debug log (#16)

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ethers-middleware/src/gas_escalator/mod.rs

@@ -251,6 +251,7 @@ impl<M, E> EscalationTask<M, E> {
  std::mem::take(&mut (*txs))
  // Lock scope ends
  };
+ println!("In the escalator watcher loop. Monitored txs: {:?}", txs);
 
  let len = txs.len();
  // Pop all transactions and re-insert those that have not been included yet