Update #ifdef ROOTVER for new the RNTuple API
The newest RNTuple API that Athena started to use now is only in ROOT ver 6.29.1 so the #ifdef protecting non-ROOT-master builds needed to be updated
ATEAM-913
Edited by Marcin Nowak
The newest RNTuple API that Athena started to use now is only in ROOT ver 6.29.1 so the #ifdef protecting non-ROOT-master builds needed to be updated
ATEAM-913