reap max bytes from the mempool & check transaction size

See ADR 020: Limiting txs size inside a block docs/architecture/adr-020-block-size.md

Refs #2035

consensus/mempool_test.go

@@ -148,7 +148,7 @@ func TestMempoolRmBadTx(t *testing.T) {
 
 		// check for the tx
 		for {
-			txs := cs.mempool.Reap(1)
+			txs := cs.mempool.ReapMaxBytes(len(txBytes))
 			if len(txs) == 0 {
 				emptyMempoolCh <- struct{}{}
 				return