docs: Update docs to inform user that mkdocs with mkdocs-material…

… must be installed in Novella Usage guide.

.changelog/_unreleased.toml

@@ -45,3 +45,12 @@ pr = "https://github.com/NiklasRosenstein/pydoc-markdown/pull/288"
 issues = [
     "https://github.com/NiklasRosenstein/pydoc-markdown/issues/286",
 ]
+
+[[entries]]
+id = "4e48b4c1-06bc-43e2-a848-870a6fa31ae3"
+type = "docs"
+description = "Update docs to inform user that `mkdocs` with `mkdocs-material` must be installed in Novella Usage guide."
+author = "@NiklasRosenstein"
+issues = [
+    "https://github.com/NiklasRosenstein/pydoc-markdown/issues/270",
+]

docs/content/usage/novella.md

@@ -40,6 +40,10 @@ What is happening here?
    source files. It will be copied to the temporary build location alongside the `mkdocs.yml` file. Note that your
    `build.novella` script should sit next two these files.
 
+   > Note: You should have `mkdocs` on your `PATH` and it should have the `mkdocs-material` theme installed (the
+   > default theme that Novella will apply if you don't specify a different one in your `mkdocs.yml` file or in
+   > `build.novella`).
+
 2. The `preprocess-markdown` action that is one of the actions created by the template is retrieved and configured
    further. We instruct it to make use of the `"pydoc"` plugin, which is implemented by Pydoc-Markdown and provides
    the `@pydoc` and `{@pylink}` tags.