Fix removal date

Author: sobolevn

Doc/library/typing.rst

@@ -894,15 +894,15 @@ using ``[]``.
       def greet_proper(cond: bool) -> str | bytes:
           return "hi there!" if cond else b"greetings!"
 
-   .. deprecated-removed:: 3.13 3.18
+   .. deprecated-removed:: 3.13 3.21
       Deprecated in favor of the new :ref:`type parameter syntax <type-params>`.
       Use ``class A[T: (str, bytes)]: ...`` instead of importing ``AnyStr``. See
       :pep:`695` for more details.
 
       Since Python 3.16, ``AnyStr`` is removed from ``typing.__all__``, and
       deprecation warnings are emitted at runtime when it is accessed or
       imported from ``typing``. ``AnyStr`` will be removed from ``typing``
-      in Python 3.18.
+      in Python 3.21.
 
 .. data:: LiteralString