Use packages of the community version of ownCloud server from here.

Packages found here belong to the latest stable release. Register this download repo to
enable auto-update to the latest features.
For production use, we have subprojects for versions 6.0, 7.0 and 8.0, so if you need a specific version release go there.
See also https://owncloud.org/release-channels/ and https://staging.owncloud.org/release-channels/