move release note entry to correct location

Author: 5chmidti

clang-tools-extra/docs/ReleaseNotes.rst

@@ -142,6 +142,10 @@ New checks
   Finds unscoped (non-class) ``enum`` declarations and suggests using
   ``enum class`` instead.
 
+- New :doc:`modernize-use-constexpr
+  <clang-tidy/checks/modernize/use-constexpr>` check that finds functions and
+  variables that can be declared `constexpr`.
+
 - New :doc:`modernize-use-scoped-lock
   <clang-tidy/checks/modernize/use-scoped-lock>` check.
 
@@ -270,10 +274,6 @@ Changes in existing checks
   excluding variables with ``thread_local`` storage class specifier from being
   matched.
 
-- Added :doc:`modernize-use-constexpr
-  <clang-tidy/checks/modernize/use-constexpr>` check that finds functions and
-  variables that can be declared `constexpr`.
-
 - Improved :doc:`modernize-use-default-member-init
   <clang-tidy/checks/modernize/use-default-member-init>` check by matching
   arithmetic operations, ``constexpr`` and ``static`` values, and detecting