Opencast 10.8

This release contains a security fix:

Further mitigation for Log4Shell (CVE-2021-45105)
Like the previous release, this is an out-of-order patch to address and resolve a further vulnerability discovered by security researchers. Unlike the previous release, it not only provides an updated version of Pax Logging, but also entirely removes the replaced bundles from Opencast's assemblies to avoid confusion if people do find the old, vulnerable version of Log4J somewhere on the filesystem, even though it is not used.