docs: add changelog and upgrade

Author: kenjis

user_guide_src/source/changelogs/v4.5.0.rst

@@ -313,6 +313,9 @@ Changes
 - **Config:**
     - ``Config\Feature::$multipleFilters`` has been removed, because now
       :ref:`multiple-filters` are always enabled.
+    - The default error level in the production environment
+      (**app/Config/Boot/production.php**) has been changed to use the same error
+      level in the development environment.
 
 Deprecations
 ************

user_guide_src/source/installation/upgrade_450.rst

@@ -255,6 +255,8 @@ The  ``'toolbar'`` in the ``$global['after']`` was removed.
 Others
 ^^^^^^
 
+- app/Config/Boot/production.php
+    - The default error level to ``error_reporting()`` has been changed to ``-1``.
 - app/Config/Database.php
     - The default value of ``charset`` in ``$default`` has been change to ``utf8mb4``.
     - The default value of ``DBCollat`` in ``$default`` has been change to ``utf8mb4_general_ci``.