ATR-30631: MET MC Menu Legacy cleanup
Removing 56 HLT items from MET MC menu and updating reference counts. The 'MET' key of chains dictionary empty for now, Phase-I triggers will be added to it later.
Removing 56 HLT items from MET MC menu and updating reference counts. The 'MET' key of chains dictionary empty for now, Phase-I triggers will be added to it later.