[ntuple] Move the RNTupleMerger out of Experimental - #23639

[ntuple] Move the RNTupleMerger out of Experimental#23639

dpiparo merged 2 commits into

root-project:masterroot-project/root:masterfrom

silverweed:ntuple_merger_out_of_expsilverweed/root:ntuple_merger_out_of_expCopy head branch name to clipboard