Remove duplicate line in whatsnew note

Author: makbigc

doc/source/whatsnew/v0.25.0.rst

@@ -251,8 +251,6 @@ Performance Improvements
 - Improved performance of nanops for dtypes that cannot store NaNs. Speedup is particularly prominent for :meth:`Series.all` and :meth:`Series.any` (:issue:`25070`)
 - Improved performance of :meth:`IntervalIndex.intersection` (:issue:`24813`)
 
->>>>>>> Add whatsnew note
-
 .. _whatsnew_0250.bug_fixes:
 
 Bug Fixes