[at-spi2-core: 5/7] Remove the old Docker scripts and update the docs

[Federico Mena Quintero <federico src gnome org>]

commit 7d3022e1a534b073a34d8c95962af62a2f8a5156
Author: Federico Mena Quintero <federico gnome org>
Date:   Tue Apr 19 19:01:37 2022 -0500

    Remove the old Docker scripts and update the docs

 ci/README.md            |  54 ++------------------
 ci/opensuse.Dockerfile  |  34 -------------
 ci/run-docker.sh        | 132 ------------------------------------------------
 devel-docs/gitlab-ci.md |   5 ++
 4 files changed, 10 insertions(+), 215 deletions(-)
---
diff --git a/ci/README.md b/ci/README.md
index 9adfaac8..7fc8697e 100644
--- a/ci/README.md
+++ b/ci/README.md
@@ -7,6 +7,10 @@ pipeline, and utilities to maintain the CI infrastructure.
 
 ## Scripts used during a run of a CI pipeline:
 
+* `container-builds.yml` - Gets included from the toplevel
+  `.gitlab-ci.yml`; has the declarations to build each container image
+  with the [Freedesktop CI Templates][ci-templates] machinery.
+
 * `run-tests.sh` - Runs the test suite and prints other diagnostics.
 
 * `gen-coverage.sh` - After the test suite is run, merges the various
@@ -24,53 +28,5 @@ pipeline, and utilities to maintain the CI infrastructure.
   `run-style-check.sh`; finds a git branch point from the current
   commit.
 
-## Utilities to maintain the CI infrastructure:
-
-To make pipelines fast, and avoid a lot of repeated downloads,
-at-spi2-core uses pre-built container images for CI pipelines, instead
-of using a stock image like opensuse/tumbleweed and then installing
-all the dependencies on top of it every time.
-
-The prebuilt images are stored here:
-https://gitlab.gnome.org/GNOME/at-spi2-core/container_registry
-
-Instead of maintaining those images by hand with `docker` or `podman`
-commands, here is a little script (stolen from [glib][glib-ci]) to
-maintain them, which you can start exploring with `./run-docker.sh help`.
-
-This script knows how to build and upload images from Dockerfiles
-called `foo.Dockerfile`.  The image configurations we have:
-
-* `opensuse.Dockerfile` - starts with an opensuse/tumbleweed image and
-  installs the package dependencies for building at-spi2-core.
-
-If you are one of at-spi2-core's maintainers, you'll want to update
-the CI images periodically.  First, install `podman` and
-`podman-docker`.  Then, run this:
-
-```sh
-# "opensuse" in these commands indicates to use the opensuse.Dockerfile configuration
-
-./run-docker.sh build --base=opensuse      # builds the image, takes a while
-
-./run-docker.sh run --base=opensuse        # launch the container; poke around; see that it works
-
-./run-docker.sh push --base=opensuse       # push the image to registry.gitlab.gnome.org
-```
-
-The `build` subcommand creates an image named
-`registry.gitlab.gnome.org/gnome/at-spi2-core/opensuse/tumbleweed:latest`
-**that is only stored in your localhost**.
-
-The `run` subcommand launches a container with that image and gives
-you a shell prompt.  This is equivalent to `podman run`.
-
-The `push` subcommand takes that built image and uploads it to
-`registry.gitlab.gnome.org`.  It will then be visible from
-https://gitlab.gnome.org/GNOME/at-spi2-core/container_registry - the
-CI configuration in [`.gitlab-ci.yml`](../.gitlab-ci.yml) uses this
-image for the pipeline.
-
 [ci-docs]: ../devel-docs/gitlab-ci.md
-[container-registry-docs]: https://gitlab.gnome.org/help/user/packages/container_registry/index
-[glib-ci]: https://gitlab.gnome.org/GNOME/glib/-/tree/main/.gitlab-ci
+[ci-templates]: https://gitlab.freedesktop.org/freedesktop/ci-templates/
diff --git a/devel-docs/gitlab-ci.md b/devel-docs/gitlab-ci.md
index 99c2f5d9..26abeeee 100644
--- a/devel-docs/gitlab-ci.md
+++ b/devel-docs/gitlab-ci.md
@@ -162,6 +162,11 @@ At-spi2-core uses CI templates to test its various build
 configurations, since it actually works differently depending on a
 distro's choice of `dbus-daemon` versus `dbus-broker`.
 
+The prebuilt container images are stored here:
+https://gitlab.gnome.org/GNOME/at-spi2-core/container_registry
+
+They get updated automatically thanks to the CI Templates machinery.
+
 # General advice and future work
 
 A failed run of a CI pipeline should trouble you; it either means that