Update doc/whatsnew again after rebasing

doc/whatsnew.rst

@@ -7,10 +7,6 @@ Next release
 - Add :doc:`/project/circeular` project code and documentation (:pull:`232`).
 - Update water availability data and major code editing to allow a new test suite for the water module (:pull:`106`).
 - Expand :doc:`repro` with sections on :ref:`repro-doc` and :ref:`versioning`, including :ref:`a list of external model names and ‘versions’ <model-names>` like “MESSAGEix-GLOBIOM 2.0” (:issue:`224`, :pull:`226`).
-- Fix and update :doc:`/api/tools-costs` (:pull:`219`)
-
-  - Fix naming of GDP and population columns in SSP data aggregation.
-
 - Update :doc:`/transport/index` (:pull:`213`).
 - Add "LED", "SSP4", and "SSP5" as values for the :program:`--ssp=…` option in :func:`.common_params` (:pull:`233`).
 - Fix and update :doc:`/api/tools-costs` (:pull:`219`, :pull:`206`)