consensus/beacon: fix blob gas error message formatting

Author: rizkyikiw42

consensus/beacon/consensus.go

@@ -258,9 +258,9 @@ func (beacon *Beacon) verifyHeader(chain consensus.ChainHeaderReader, header, pa
 	if !cancun {
 		switch {
 		case header.ExcessBlobGas != nil:
-			return fmt.Errorf("invalid excessBlobGas: have %d, expected nil", header.ExcessBlobGas)
+			return fmt.Errorf("invalid excessBlobGas: have %d, expected nil", *header.ExcessBlobGas)
 		case header.BlobGasUsed != nil:
-			return fmt.Errorf("invalid blobGasUsed: have %d, expected nil", header.BlobGasUsed)
+			return fmt.Errorf("invalid blobGasUsed: have %d, expected nil", *header.BlobGasUsed)
 		case header.ParentBeaconRoot != nil:
 			return fmt.Errorf("invalid parentBeaconRoot, have %#x, expected nil", header.ParentBeaconRoot)
 		}