Upgrade to Jackrabbit 2.18.3 and Tika 1.22

Update our patched jackrabbit to the latest maintenance release of the upstream Jackrabbit 2.18.3. This update also includes an update to Tika from 1.20 to 1.22, which we should account for in our dependency management.

Note: Tika 1.22 adds a dependency to Xerces, which we definitely do NOT want in our product. We must explicitly exclude it.