Reduce threshold for block validity

Author: howardwu

ledger/block/src/lib.rs

@@ -159,12 +159,6 @@ impl<N: Network> Block<N> {
             );
         }
 
-        // Ensure the block contains transactions.
-        ensure!(
-            !transactions.is_empty() || !aborted_transaction_ids.is_empty(),
-            "Cannot create a block with zero transactions"
-        );
-
         // Ensure the number of transactions is within the allowed range.
         if transactions.len() > Transactions::<N>::MAX_TRANSACTIONS {
             bail!(