Elton John canceled two upcoming shows in Dallas after testing positive for COVID. The “I’m Still Standing” singer expressed regret for not being able to perform on Tuesday or Wednesday, but assured fans he followed the science and expects to be on the road to resume his “Farewell Yellow Brick Road” tour soon. “Fortunately I’m fully vaccinated and boosted and my symptoms are mild so I’m fully expecting to make the Arkansas shows this weekend,” the 74-year-old hit-maker wrote on Instagram. He apologized for the inconvenience, adding that he’s trying to keep himself and his team safe. As the tou…