进入到你的flutter安装目录
类似这种 /Users//Documents/flutter_sdk_1.12.13/flutter
然后运行下面
git reset --hard 9b2d32b605630f28625709ebd9d78ab3016b2bf6
解释一下9b2d32b605630f28625709ebd9d78ab3016b2bf6
9b2d32b605630f28625709ebd9d78ab3016b2bf6 这个是 Flutter Stable 1.22.6 的commit
然后你再执行发flutter doctor就行了,当然记得开梯子