Adds what's new entry

Author: oguzhanogreden

doc/source/whatsnew/v1.0.0.rst

@@ -336,7 +336,8 @@ Numeric
 - Bug in :class:`DataFrame` logical operations (`&`, `|`, `^`) not matching :class:`Series` behavior by filling NA values (:issue:`28741`)
 - Bug in :meth:`DataFrame.interpolate` where specifying axis by name references variable before it is assigned (:issue:`29142`)
 - Improved error message when using `frac` > 1 and `replace` = False (:issue:`27451`)
--
+- Bug in :class:`UInt64Index` precision loss while constructing from a list with values in the ``np.uint64`` range (:issue:`29526`)
+- 
 
 Conversion
 ^^^^^^^^^^