update changelog to fix an indentation error

Author: hossam26644

python/CHANGELOG.rst

@@ -8,8 +8,9 @@
   the original schema instead (:user:`benjeffery`, :issue:`3129`, :pr:`3130`)
 
 **Breaking Changes**
-- Legacy formats from msprime<0.6 (HDF5 formats) support is dropped. This includes the support for
-  ``tskit upgrade``  (:user:`hossam26644`, :issue:`2812`, :pr:`3138`)
+
+- Legacy formats from msprime<0.6 (HDF5 formats) support is dropped. This includes the
+  support for ``tskit upgrade``  (:user:`hossam26644`, :issue:`2812`, :pr:`3138`)
 
 --------------------
 [0.6.1] - 2025-03-31