feature: Add opencloud api to integration

[suse-coder]

Currently Windmill only support basic nextcloud api function. As Opencloud (formerly owncloud infinit scale) is very popular now and many switch to it, it would be great to have a api support for that (like https://www.windmill.dev/docs/integrations/nextcloud).

Please support these three apis: • Graph API • WebDAV / OCDAV • OCS

https://doc.owncloud.com/ocis/next/deployment/services/s-list/graph.html https://doc.owncloud.com/ocis/next/deployment/services/s-list/webdav.html