bpo-38291: Remove mention of typing.io and typing.re again (GH-26113)

They were originally removed in GH-10173 per bpo-35089, but then
readded in GH-21574. Cf. bpo-38291 for decision to remove.

Author: srittau

Doc/library/typing.rst

@@ -1488,7 +1488,11 @@ Other concrete types
    Generic type ``IO[AnyStr]`` and its subclasses ``TextIO(IO[str])``
    and ``BinaryIO(IO[bytes])``
    represent the types of I/O streams such as returned by
-   :func:`open`. These types are also in the ``typing.io`` namespace.
+   :func:`open`.
+
+   .. deprecated-removed:: 3.8 3.12
+      These types are also in the ``typing.io`` namespace, which was
+      never supported by type checkers and will be removed.
 
 .. class:: Pattern
            Match
@@ -1498,7 +1502,11 @@ Other concrete types
    :func:`re.match`.  These types (and the corresponding functions)
    are generic in ``AnyStr`` and can be made specific by writing
    ``Pattern[str]``, ``Pattern[bytes]``, ``Match[str]``, or
-   ``Match[bytes]``. These types are also in the ``typing.re`` namespace.
+   ``Match[bytes]``.
+
+   .. deprecated-removed:: 3.8 3.12
+      These types are also in the ``typing.re`` namespace, which was
+      never supported by type checkers and will be removed.
 
    .. deprecated:: 3.9
       Classes ``Pattern`` and ``Match`` from :mod:`re` now support ``[]``.

Misc/NEWS.d/next/Documentation/2021-06-14-09-20-37.bpo-38291.VMYa_Q.rst

@@ -0,0 +1,2 @@
+Mark ``typing.io`` and ``typing.re`` as deprecated since Python 3.8 in the
+documentation. They were never properly supported by type checkers.