跳过flutter私有库发布验证 使用方法 1、把文件拷贝到dart-sdk/bin/snapshots中 2、修改dart-sdk/bin/pub文件 用记事本打开 3、SNAPSHOT="$BIN_DIR/snapshots/pub.dart.snapshot" 修改为SNAPSHOT="$BIN_DIR/snapshots/mypub.dart.snapshot"