Update site.nextcloud.custom

fix file upload size limit

data/assets/nextcloud/site.nextcloud.custom

@@ -19,6 +19,7 @@
       fastcgi_pass phpfpm:9000;
       fastcgi_intercept_errors on;
       fastcgi_request_buffering off;
+      client_max_body_size 10G;
     }
     location ~ ^/nextcloud/(?:updater|ocs-provider)(?:$|/) {
       try_files $uri/ =404;