Use correct env var syntax

var/www/explorer.hush.land/update_api.sh

@@ -1,10 +1,10 @@
 #!/usr/bin/env bash
 # Copyright 2016-2022 The Hush Developers
 
-DOMAIN=$(SIONA_DOMAIN)
-CLI=$(SIONA_CLI)
+DOMAIN=${SIONA_DOMAIN}
+CLI=${SIONA_CLI}
 # this is optional and not used yet here
-ACNAME=$(SIONA_ACNAME)
+ACNAME=${SIONA_ACNAME}
 DIR=/var/www/$DOMAIN/var/www/$DOMAIN/api
 
 # TODO: remove IP info from getpeerinfo