Remove metadata support for TAGs, which have not been supported for ages.

TAGs have never really been used, nor is the metadata supported there. This adds needless complexity to the code, so time to remove.

LumiBlock/LumiBlockComps/Root/LumiBlockMetaDataTool.cxx

@@ -12,8 +12,6 @@
 #include "GoodRunsLists/TGoodRunsListReader.h"
 #include "xAODLuminosity/SortLumiBlockRangeByStart.h"
 
-#include "DBDataModel/CollectionMetadata.h"
-
 #include "GoodRunsLists/TGoodRunsList.h"
 
 #include "TROOT.h"