docs/devel: remind developers to run CI container pipeline when updating images

docs/devel: remind developers to run CI container pipeline when updating images

When new dependencies and packages are added to containers, its important to
run CI container generation pipelines on gitlab to make sure that there are no
obvious conflicts between packages that are being added and those that are
already present. Running CI container pipelines will make sure that there are
no such breakages before we commit the change updating the containers. Add a
line in the documentation reminding developers to run the pipeline before
submitting the change. It will also ease the life of the maintainers.

Signed-off-by: Ani Sinha <anisinha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230506072012.10350-1-anisinha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-5-alex.bennee@linaro.org>