docs(whatsnew): add entry

Author: Alvaro-Kothe

doc/source/whatsnew/v3.0.0.rst

@@ -1148,6 +1148,7 @@ Other
 - Bug in :meth:`Series.diff` allowing non-integer values for the ``periods`` argument. (:issue:`56607`)
 - Bug in :meth:`Series.dt` methods in :class:`ArrowDtype` that were returning incorrect values. (:issue:`57355`)
 - Bug in :meth:`Series.isin` raising ``TypeError`` when series is large (>10**6) and ``values`` contains NA (:issue:`60678`)
+- Bug in :meth:`Series.kurt` resulting in zero for low variance arrays (:issue:`57972`)
 - Bug in :meth:`Series.map` with a ``timestamp[pyarrow]`` dtype or ``duration[pyarrow]`` dtype incorrectly returning all-``NaN`` entries (:issue:`61231`)
 - Bug in :meth:`Series.mode` where an exception was raised when taking the mode with nullable types with no null values in the series. (:issue:`58926`)
 - Bug in :meth:`Series.rank` that doesn't preserve missing values for nullable integers when ``na_option='keep'``. (:issue:`56976`)