Draft: Fix getting the keys from SgTEventMeta and recording metadata objects in TEvent
This fixes the issue reported in https://atlas-talk.web.cern.ch/t/issue-with-filemetadata-tool-in-analysisbase/45623
This fixes the issue reported in https://atlas-talk.web.cern.ch/t/issue-with-filemetadata-tool-in-analysisbase/45623