gh-123621: Fix datamodel.rst with proper dict notation (#123648)

Author: AttilaLiptak

Doc/reference/datamodel.rst

@@ -499,7 +499,7 @@ in the same order they were added sequentially over the dictionary.
 Replacing an existing key does not change the order, however removing a key
 and re-inserting it will add it to the end instead of keeping its old place.
 
-Dictionaries are mutable; they can be created by the ``{...}`` notation (see
+Dictionaries are mutable; they can be created by the ``{}`` notation (see
 section :ref:`dict`).
 
 .. index::