Doc: recursive glob ** follows symlinks to directories (GH-12918)

(cherry picked from commit e24594b)

Co-authored-by: Marc <Marc.Herbert+github@gmail.com>

Author: miss-islington

Doc/library/glob.rst

@@ -48,8 +48,9 @@ For example, ``'[?]'`` matches the character ``'?'``.
       single: **; in glob-style wildcards
 
    If *recursive* is true, the pattern "``**``" will match any files and zero or
-   more directories and subdirectories.  If the pattern is followed by an
-   ``os.sep``, only directories and subdirectories match.
+   more directories, subdirectories and symbolic links to directories. If the
+   pattern is followed by an :data:`os.sep` or :data:`os.altsep` then files will not
+   match.
 
    .. note::
       Using the "``**``" pattern in large directory trees may consume