Update owncloud-dolphin to version 6.0.0 / rev 2 via SR 1250567
    
    https://build.opensuse.org/request/show/1250567
    by user Vogtinator + anag+factory
    Add changelog from git to make it pass factory review
    
    - Updated to 6.0.0
    - Changes since 5.0.0:
      * Set a project version
      * Cleanup
      * Depend on the icons to be present
      * Use a tumbleweed container in Ubuntu for CI to build with KF6
      * Different split code to satisfy review
      * Use pragma once consistently and add license header
      * Fix workflow description: Use Ubu 24.04 and use KF6
      * Update README
      * Cleanups, fixed the json.in
      * Port to KF6, splitting a header for the action plugin (forwarded request 1250246 from Vogtinator)