Webdav upload to S3 external storage not in chunk v2

⚠️ This issue respects the following points: ⚠️ • This is not a troubleshooting question, general support matter, or webserver/proxy problem, but likely a bug _(if unsure, ask the [Community Help Forum]( • This issue is not already reported on [Github]( OR solved at the [Community Help Forum]( _(I've searched!)_. • I'm using a maintained major version of Nextcloud Server and tested against the latest patch level. _([Supported major versions and current patch levels]( • I agree to follow Nextcloud's [Code of Conduct]( • I've tried my best to provide clear reproduction steps that someone unfamiliar with this bug could use to reproduce it. Bug description When uploading a large file as chunked v2 mode, with a nextcloud server using S3 as external storage (not primary storage), the server does not proceed to chunk v2 and fallback to chunk v1. Thus the file is in the server disk twice the size (one as chunks in "upload" of the …