Apply suggestions from code review

Author: JuArce

crates/sdk/src/common/errors.rs

@@ -221,7 +221,7 @@ impl fmt::Display for SubmitError {
             }
             SubmitError::ProofReplaced => write!(
                 f,
-                "Proof has been replaced by a higher fee for the same proof"
+                "Proof has been replaced by a higher fee for the same nonce"
             ),
             SubmitError::GetNonceError(e) => write!(f, "Error while getting nonce {}", e),
             SubmitError::UserFundsUnlocked => write!(

crates/sdk/src/communication/messaging.rs

@@ -280,7 +280,7 @@ async fn handle_batcher_response(msg: Message) -> Result<BatchInclusionData, Sub
             Err(SubmitError::UserFundsUnlocked)
         }
         Ok(SubmitProofResponseMessage::ProofReplaced) => {
-            error!("Proof has been replaced by a higher fee for the same proof. Funds have not been spent.");
+            error!("Proof has been replaced by a higher fee for the same nonce. Funds have not been spent.");
             Err(SubmitError::ProofReplaced)
         }
         Err(e) => {