6.5.1: Add release notes (#3420)
6.5.1: Add release notes (#3420)

* 6.5.1: Add release notes

* Update date

* Update date

Co-authored-by: James Phillips <1689973a284c5efe14b126317ec1cb93c4da1cdd@gmail.com>

Co-authored-by: James Phillips <1689973a284c5efe14b126317ec1cb93c4da1cdd@gmail.com>
sensu/sensu-docs,sensu/sensu-docs,sensu/sensu-docs,sensu/sensu-docs,sensu/sensu-docs