Upgrade tested version of WooCommerce

Author: Daniel Fjeldstad

README.md

@@ -34,7 +34,7 @@ Optional plugin:
 The current release has been tested and is confirmed working with the following versions:
 
 - WordPress version 5.8.0
-- WooCommerce version 5.5.1
+- WooCommerce version 5.9.0
 - WP GraphQL version 1.2.4
 - WooGraphQL version 0.6.1