fix(l1): show proper exported number of blocks (#5448)

**Motivation**

The range blocks showed on the export of blocks on ethrex is inclusive
of first and last block, but the number reported is (end - start). This
pr aims to rectify this.

**Description**

- This PR adds a 1 to the reported number to make it accurate.

Author: fedacking

cmd/ethrex/cli.rs

@@ -842,5 +842,5 @@ pub async fn export_blocks(
         file.write_all(&buffer).expect("Failed to write to file");
         buffer.clear();
     }
-    info!(blocks = end.saturating_sub(start), path = %path, "Exported blocks to file");
+    info!(blocks = end.saturating_sub(start) + 1, path = %path, "Exported blocks to file");
 }