util/docker: Update dockerfiles

- Remove deprecated "MAINTAINER" lines
- Add Sphinx tools to coreboot-jenkins-node to check documentation.
- Add mdl to check markdown
- Alphabetize packages in docs Dockerfile
- Add jinja2 version 3.0.3 to the docs Dockerfile - The latest version
breaks with the error:
"exception: cannot import name 'contextfunction' from 'jinja2'"

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: Ia1de62621a6aef4ecd055a1a3afbebad34448002
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64655
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <felixsinger@posteo.net>

0 files changed, 0 insertions, 0 deletions