Update "Tested up to" to 6.5

README.md

@@ -1,12 +1,12 @@
 # Co-Authors Plus
 
-Stable tag: 3.6.0  
-Requires at least: 4.1  
-Tested up to: 6.3  
-Requires PHP: 5.6  
-License: GPLv2 or later  
-License URI: https://www.gnu.org/licenses/gpl-2.0.html  
-Tags: authors, users, multiple authors, co-authors, multi-author, publishing  
+Stable tag: 3.6.0
+Requires at least: 4.1
+Tested up to: 6.5
+Requires PHP: 5.6
+License: GPLv2 or later
+License URI: https://www.gnu.org/licenses/gpl-2.0.html
+Tags: authors, users, multiple authors, co-authors, multi-author, publishing
 Contributors: batmoo, danielbachhuber, automattic, GaryJ
 
 Assign multiple bylines to posts, pages, and custom post types with a search-as-you-type input box.