The indexing of steps in the output of `docker build` starts with `Step 1`. However, there are several places in the docs that start with `Step 0`. This fix addresses the issue and changes `Step 0` to `Step 1` (and subsequent steps). Signed-off-by: Yong Tang <yong.tang.github@outlook.com> Upstream-commit: 256dbe4b752ba1fde88e6fad76e3a6b08e4a8816 Component: engine