message: TechDocs: Update docs around docker-in-docker installation
  Fix python package name to mkdocs-techdocs-core
  Refer to the original Dockerfile where users can seek inspiration from
diff: @@ -73,10 +73,10 @@ required.
  ### Disable Docker in Docker situation (Optional)
  -The TechDocs backend plugin runs a docker container with mkdocs to generate the
  -frontend of the docs from source files (Markdown). If you are deploying
  -Backstage using Docker, this will mean that your Backstage Docker container will
  -try to run another Docker container for TechDocs backend.
  +The TechDocs backend plugin runs a docker container with mkdocs installed to
  +generate the frontend of the docs from source files (Markdown). If you are
  +deploying Backstage using Docker, this will mean that your Backstage Docker
  +container will try to run another Docker container for TechDocs backend.
  To avoid this problem, we have a configuration available. You can set a value in
  your `app-config.yaml` that tells the techdocs generator if it should run the
  @@ -90,10 +90,16 @@ techdocs:
  ```
  Setting `generators.techdocs` to `local` means you will have to make sure your
  -environment is compatible with techdocs. You will have to install the
  -`mkdocs-techdocs-container` and 'mkdocs' package from pip, as well as graphviz
  -and plantuml from your package manager. This has only been tested with python
  -3.7 and python 3.8.
  +environment is compatible with techdocs.
  +
  +You will have to install the `mkdocs-techdocs-core` and `mkdocs` package from
  +pip, as well as `graphviz` and `plantuml` from your OS package manager (e.g.
  +apt). See our
  +[Dockerfile](https://github.com/spotify/backstage/blob/master/packages/techdocs-container/Dockerfile)
  +for the latest requirements. You should be trying to match your Dockerfile with
  +this one.
  +
  +It is worth mentioning that we recommend Python version 3.7 or higher.
  ## Run Backstage locally
  