Merge topic 'doc-fix-CMAKE_MESSAGE_INDENT-sample-output'

493b8eae36 Help: Fix example output in the `CMAKE_MESSAGE_INDENT` documentation

Acked-by: Kitware Robot <[email protected]>
Merge-request: !3651

Help/variable/CMAKE_MESSAGE_INDENT.rst

@@ -23,6 +23,8 @@ Example:
 
 Which results in the following output:
 
+.. code-block:: none
+
   -- Collected items in the "listVar":
   --   one
   --   two