* edit: updated `Security scanning` section
`docker scan` fails when user is not logged in to Docker Hub. First I had to use `docker login` to login to Docker Hub. Afterwards, `docker scan` worked.
* Update 09_image_best.md
Update format, fix a typo
Co-authored-by: Usha Mandya <47779042+usha-mandya@users.noreply.github.com>
BuildKit allows using alternative Dockerfile syntaxes to introduce new features
without having to update Docker itself. The general recommendation is to always
specify a "syntax" directive in a Dockerfile, so that (if needed) older versions
of Docker can download the correct syntax to build the Dockerfile.
This updates our examples to include a syntax directive, to make users more familiar
with these directives, and to illustrate best-pracitces in our documentation.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>