DORTMUND, Germany — Borussia Dortmund signed Algeria international Ramy Bensebaini on a free transfer from Borussia Mönchengladbach, making the left back its first reinforcement of the summer on Monday. Bensebaini replaces Portugal left back Raphaël Guerreiro, who also allowed his contract expire, and Dortmund said that the 28-year-old Bensebaini had signed a four-year deal. “Ramy is a player in his …