Backport PR #43520: DOC: 1.3.3 release date (#43521)

Co-authored-by: Simon Hawkins <simonjayhawkins@gmail.com>

doc/source/whatsnew/v1.3.3.rst

@@ -1,6 +1,6 @@
 .. _whatsnew_133:
 
-What's new in 1.3.3 (September ??, 2021)
+What's new in 1.3.3 (September 12, 2021)
 ----------------------------------------
 
 These are the changes in pandas 1.3.3. See :ref:`release` for a full changelog
@@ -15,7 +15,6 @@ including other versions of pandas.
 Fixed regressions
 ~~~~~~~~~~~~~~~~~
 - Fixed regression in :class:`DataFrame` constructor failing to broadcast for defined :class:`Index` and len one list of :class:`Timestamp` (:issue:`42810`)
-- Performance regression in :meth:`core.window.ewm.ExponentialMovingWindow.mean` (:issue:`42333`)
 - Fixed regression in :meth:`.GroupBy.agg` incorrectly raising in some cases (:issue:`42390`)
 - Fixed regression in :meth:`.GroupBy.apply` where ``nan`` values were dropped even with ``dropna=False`` (:issue:`43205`)
 - Fixed regression in :meth:`.GroupBy.quantile` which was failing with ``pandas.NA`` (:issue:`42849`)
@@ -29,8 +28,8 @@ Fixed regressions
 - Fixed regression in :meth:`DataFrame.corr` where Kendall correlation would produce incorrect results for columns with repeated values (:issue:`43401`)
 - Fixed regression in :meth:`DataFrame.groupby` where aggregation on columns with object types dropped results on those columns (:issue:`42395`, :issue:`43108`)
 - Fixed regression in :meth:`Series.fillna` raising ``TypeError`` when filling ``float`` ``Series`` with list-like fill value having a dtype which couldn't cast lostlessly (like ``float32`` filled with ``float64``) (:issue:`43424`)
-- Fixed regression in :func:`read_csv` throwing an ``AttributeError`` when the file handle is an ``tempfile.SpooledTemporaryFile`` object (:issue:`43439`)
--
+- Fixed regression in :func:`read_csv` raising ``AttributeError`` when the file handle is an ``tempfile.SpooledTemporaryFile`` object (:issue:`43439`)
+- Fixed performance regression in :meth:`core.window.ewm.ExponentialMovingWindow.mean` (:issue:`42333`)
 
 .. ---------------------------------------------------------------------------
 
@@ -39,26 +38,14 @@ Fixed regressions
 Performance improvements
 ~~~~~~~~~~~~~~~~~~~~~~~~
 - Performance improvement for :meth:`DataFrame.__setitem__` when the key or value is not a :class:`DataFrame`, or key is not list-like (:issue:`43274`)
--
--
 
 .. ---------------------------------------------------------------------------
 
 .. _whatsnew_133.bug_fixes:
 
 Bug fixes
 ~~~~~~~~~
-- Bug in :meth:`.DataFrameGroupBy.agg` and :meth:`.DataFrameGroupBy.transform` with ``engine="numba"`` where ``index`` data was not being correctly passed into ``func`` (:issue:`43133`)
--
-
-.. ---------------------------------------------------------------------------
-
-.. _whatsnew_133.other:
-
-Other
-~~~~~
--
--
+- Fixed bug in :meth:`.DataFrameGroupBy.agg` and :meth:`.DataFrameGroupBy.transform` with ``engine="numba"`` where ``index`` data was not being correctly passed into ``func`` (:issue:`43133`)
 
 .. ---------------------------------------------------------------------------