Adding changelog item

Modules/Core/changelog.yml

@@ -14,6 +14,7 @@ versions:
             - Update the message displayed while the admin user is created.
             - Fixed issue when <code>hideDefaultLocaleInURL</code> was set to true making VueJS routes not working
             - Removed default loading of unneeded assets
+            - Getting pdo object, making sure the database connection is valid
     "3.0.0":
         added:
             - Created a vue component for the delete buttons on index pages