Define reload CMD for mail.nasqueron.org certificate

Summary:
This will permit to launch the reload script for Dovecot and Postfix

Ref T2196

Test Plan: deploy the reload cmd and make acme reload the certificate

Reviewers: dereckson

Reviewed By: dereckson

Maniphest Tasks: T2196

Differential Revision: https://devcentral.nasqueron.org/D4005