docs/devel: add intended audience to docs tutorial

docs/contributing/tutorial-docs-contribution.rst

@@ -3,6 +3,12 @@
 Tutorial: Best practices when writing SWH docs
 ==============================================
 
+.. admonition:: Intended audience
+   :class: important
+
+   Members of the Software Heritage staff and external contributors
+   who wish to contribute by writing documentation.
+   
 A tutorial on how to contribute documentation into the Software Heritage world.
 
 Step 1: Identify your audience
@@ -123,6 +129,11 @@ Empty page template
    Empty page
    ==========
 
+   .. admonition:: Intended audience
+      :class: important
+
+      add the audience target(s) of this page
+   
    .. todo::
       This page is a work in progress. For now, please refer to the `existing documentation <https://...>`_.