Issue #25508: Clarify documentation on LogRecord args attribute.

Doc/library/logging.rst

@@ -738,7 +738,9 @@ the options available to you.
 | Attribute name | Format                  | Description                                   |
 +================+=========================+===============================================+
 | args           | You shouldn't need to   | The tuple of arguments merged into ``msg`` to |
-|                | format this yourself.   | produce ``message``.                          |
+|                | format this yourself.   | produce ``message``, or a dict whose values   |
+|                |                         | are used for the merge (when there is only one|
+|                |                         | argument, and it is a dictionary).            |
 +----------------+-------------------------+-----------------------------------------------+
 | asctime        | ``%(asctime)s``         | Human-readable time when the                  |
 |                |                         | :class:`LogRecord` was created.  By default   |