Revert "core/txpool : fix map size avoid resizing (ethereum#27221)"

This reverts commit cd43de7.

core/txpool/txpool.go

@@ -549,7 +549,7 @@ func (pool *TxPool) Pending(enforceTips bool) map[common.Address]types.Transacti
 	pool.mu.Lock()
 	defer pool.mu.Unlock()
 
-	pending := make(map[common.Address]types.Transactions, len(pool.pending))
+	pending := make(map[common.Address]types.Transactions)
 	for addr, list := range pool.pending {
 		txs := list.Flatten()