Update RootUtils.py - fix failing test (checkMetaSG_test) ... seems like new...

Update RootUtils.py - fix failing test (checkMetaSG_test) ... seems like new ROOT code is needed in 6.12 too: http://atlas-computing.web.cern.ch/atlas-computing/links/distDirectory/gitwww/GITWebArea/.testn/21.2/2018-12-11T0325/AthAnalysis/x86_64-slc6-gcc62-opt/AthAnalysis//art.log.html

Former-commit-id: 4197e684231168916af607b65870c15afa60e029

Tools/PyUtils/python/RootUtils.py

@@ -30,7 +30,7 @@ from .Decorators import memoize
 # Set buffer size, in bytes.
 # The argument to SetSize is in elements, not bytes.
 def _set_byte_size (buf, sz):
-    if ROOT.gROOT.GetVersionInt() >= 61400:
+    if ROOT.gROOT.GetVersionInt() >= 61200:
         eltsz = array(buf.typecode).itemsize
         buf.SetSize (sz / eltsz)
     else: