This location block in Nextcloud NGINX config should fix the warning
location ~ ^/(?:updater|oc[ms]-provider)(?:$|/) {
try_files $uri/ =404;
index index.php;
}
just copy and past those lines in Nextcloud NGINX config, L.106 and restart NGINX service.
The warning should disappear.
A fix is on the way but it might be nice to test it first.