Fix sphinx formatting in changelog
@@ -10,7 +10,7 @@ New features
Bugfixes
--------
-- The multistate samplers now issue experimental API warnings via `logger.warn()` rather than `warnings.warn()` (#446)
+- The multistate samplers now issue experimental API warnings via ``logger.warn()`` rather than ```warnings.warn()`` (`#446 <https://github.com/choderalab/openmmtools/pull/446>`_)
0.18.3 - Storage enhancements and bugfixes
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