Doc: fix a rst tag. (GH-26965)

Author: JulienPalard

Doc/library/contextlib.rst

@@ -515,9 +515,9 @@ Functions and classes provided:
       These context managers may suppress exceptions just as they normally
       would if used directly as part of a :keyword:`with` statement.
 
-      ... versionchanged:: 3.11
-          Raises :exc:`TypeError` instead of :exc:`AttributeError` if *cm*
-          is not a context manager.
+      .. versionchanged:: 3.11
+         Raises :exc:`TypeError` instead of :exc:`AttributeError` if *cm*
+         is not a context manager.
 
    .. method:: push(exit)
 
@@ -589,9 +589,9 @@ Functions and classes provided:
       Similar to :meth:`enter_context` but expects an asynchronous context
       manager.
 
-      ... versionchanged:: 3.11
-          Raises :exc:`TypeError` instead of :exc:`AttributeError` if *cm*
-          is not an asynchronous context manager.
+      .. versionchanged:: 3.11
+         Raises :exc:`TypeError` instead of :exc:`AttributeError` if *cm*
+         is not an asynchronous context manager.
 
    .. method:: push_async_exit(exit)