Docsite: improve developing_modules_documenting.rst (#71590)

* Docsite: improve developing_modules_documenting.rst

* add necessary dots to returns descriptions

docs/docsite/rst/dev_guide/developing_modules_documenting.rst

@@ -330,13 +330,15 @@ Per playbook best practices, each example should include a ``name:`` line::
 
     EXAMPLES = r'''
     - name: Ensure foo is installed
-      modulename:
+      namespace.collection.modulename:
         name: foo
         state: present
     '''
 
 The ``name:`` line should be capitalized and not include a trailing dot.
 
+Use a fully qualified collection name (FQCN) as a part of the module's name like in the example above. For modules in ``ansible-base``, use the ``ansible.builtin.`` identifier, for example ``ansible.builtin.debug``.
+
 If your examples use boolean options, use yes/no values. Since the documentation generates boolean values as yes/no, having the examples use these values as well makes the module documentation more consistent.
 
 If your module returns facts that are often needed, an example of how to use them can be helpful.
@@ -392,12 +394,12 @@ Here are two example ``RETURN`` sections, one with three simple fields and one w
 
     RETURN = r'''
     packages:
-        description: Information about package requirements
+        description: Information about package requirements.
         returned: success
         type: complex
         contains:
             missing:
-                description: Packages that are missing from the system
+                description: Packages that are missing from the system.
                 returned: success
                 type: list
                 sample: