Change X-NC-WebDAV-AutoMkcol to X-NC-WebDAV-Auto-Mkcol

[VidarHook]

Before You Submit

• I have checked for existing issues and pull requests related to my suggestion.
• I have posted on the Nextcloud Community Help Forum if my suggestion is a troubleshooting scenario or I'm unsure about the solution.

Type of Suggestion

Reporting a mistake

Relevant Documentation Links

https://github.com/nextcloud/documentation/blob/master/developer_manual/client_apis/WebDAV/basic.rst#L615

Summary

X-NC-WebDAV-AutoMkcol is wrong, it should be Auto-Mkcol

Details

See: https://github.com/nextcloud/server/blob/master/apps/dav/lib/Upload/UploadAutoMkcolPlugin.php#L41

Kept getting 403 when trying to push the fix myself, so I just posted an issue instead.

Additional Notes

No response