This hook will copy the key and certificate chain to the specified
mailcow installation (as described in
https://mailcow.github.io/mailcow-dockerized-docs/firststeps-ssl/#use-own-certificates)
and restarts the containers, that are using the certificates.
The hook has 2 parameters:
* `DEPLOY_MAILCOW_PATH`: The path to the mailcow installation (required)
* `DEPLOY_MAILCOW_RELOAD`: The reload command, defaults to `docker-compose restart postfix-mailcow dovecot-mailcow nginx-mailcow`
