root path for the base domain

roles/matrix-nginx-proxy/templates/nginx/conf.d/matrix-base-domain.conf.j2

@@ -1,7 +1,7 @@
 #jinja2: lstrip_blocks: "True"
 
 {% macro render_vhost_directives() %}
-	root /nginx-data/matrix-domain;
+	root {{ matrix_nginx_proxy_data_path }}/matrix-domain;
 
 	gzip on;
 	gzip_types text/plain application/json;