Added an entry in the latest doc/source/whatsnew/v3.0.0.rst

Author: xaris96

doc/source/whatsnew/v3.0.0.rst

@@ -744,6 +744,8 @@ Indexing
 - Bug in :meth:`MultiIndex.insert` when a new value inserted to a datetime-like level gets cast to ``NaT`` and fails indexing (:issue:`60388`)
 - Bug in printing :attr:`Index.names` and :attr:`MultiIndex.levels` would not escape single quotes (:issue:`60190`)
 - Bug in reindexing of :class:`DataFrame` with :class:`PeriodDtype` columns in case of consolidated block (:issue:`60980`, :issue:`60273`)
+- Bug in :class:`Index` methods when handling mixed integer and string values (e.g. ``Index([0, "a", 1, "b", 2, "c"])``) uncovered by new test case (:issue:`54072`)
+
 
 Missing
 ^^^^^^^