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: 98043e3f79
Component: cli