DOCS update whatsnew with DataFrame.aggregate bugfix

Author: AdrianoCLeao

doc/source/whatsnew/v3.0.0.rst

@@ -932,6 +932,7 @@ Other
 - Bug in ``Series.list`` methods not preserving the original name. (:issue:`60522`)
 - Bug in printing a :class:`DataFrame` with a :class:`DataFrame` stored in :attr:`DataFrame.attrs` raised a ``ValueError`` (:issue:`60455`)
 - Bug in printing a :class:`Series` with a :class:`DataFrame` stored in :attr:`Series.attrs` raised a ``ValueError`` (:issue:`60568`)
+- Bug in :meth:`DataFrame.aggregate` dropping pyarrow backend for lambda aggregation functions (:issue:`61812`)
 - Fixed bug where the :class:`DataFrame` constructor misclassified array-like objects with a ``.name`` attribute as :class:`Series` or :class:`Index` (:issue:`61443`)
 - Fixed regression in :meth:`DataFrame.from_records` not initializing subclasses properly (:issue:`57008`)