Fix codecov to use gcov reports instead of llvm-cov
Fix codecov to use gcov reports instead of llvm-cov

rs/SDWebImage,dreampiggy/SDWebImage,dreampiggy/SDWebImage,awkward/SDWebImage,awkward/SDWebImage,tualatrix/SDWebImage,dreampiggy/SDWebImage,zhang-yawei/SDWebImage,awkward/SDWebImage