Add jq, and update outdated documentation (#283)

README.md

@@ -21,7 +21,15 @@ This tutorial covers basic to advanced usage, packaging, developer features, and
 
 ## Updating the tutorial container
 
-The Spack tutorial container is built from another [repository](https://github.com/spack/spack-tutorial-container) by an automated process.  For instructions on how to create an updated version of the tutorial container, see these [instructions](https://github.com/spack/spack-tutorial-container/blob/master/UPDATING.md).  For a general description of the automated process used to build the tutorial container, read the [description](https://github.com/spack/spack-tutorial-container/blob/master/DESCRIPTION.md).
+The Spack tutorial container is automatically built from [repository](docker/Dockerfile) by [this GitHub action](.github/workflows/containers.yaml). The latest version is available at
+
+```
+ghcr.io/spack/tutorial:latest
+```
+
+and is rebuilt on a schedule. It can also be [triggered manually](https://github.com/spack/spack-tutorial/actions).
+
+The tutorial image builds on top of the container image that runs in Spack CI, which is built in a different repository at [spack/gitlab-runners](https://github.com/spack/gitlab-runners/)
 
 ## Automatically generating command ouputs
 

docker/Dockerfile

@@ -32,7 +32,7 @@ COPY /concretizer.yaml /etc/spack/concretizer.yaml
 
 RUN DEBIAN_FRONTEND=noninteractive apt-get remove -y gcc-12 && \
     apt-get update -y && \
-    apt-get install -y --no-install-recommends emacs bash-completion less && \
+    apt-get install -y --no-install-recommends emacs bash-completion less jq && \
     apt-get -y autoremove --purge && \
     apt-get clean