PARIS—Czech Barbora Krejcikova said she was going to enjoy a rare glass of champagne on Sunday after completing a singles-doubles title sweep at the French Open by taking the women’s doubles trophy with compatriot Katerina Siniakova. Krejcikova became the first player to win both the women’s singles and doubles title in Paris since Frenchwoman Mary Pierce completed the feat in 2000 after the Czech duo beat Iga Swiatek and Bethanie Mattek-Sands 6-4 6-2. The 25-year-old Krejcikova, who will climb to 15th in singles following her maiden Grand Slam singles title on Saturday, will return as the world number one doubles player when the rankings are updated on Monday. “I think we are going to have a dinner together this evening,” she told reporters. “We will have a little bit glass of champagne. I already said I don’t really drink but I think it’s a time to actually celebrate it. I …