ATLASRECTS-6316,ATEAM-742 : PFNeutralFlowElementCreatorAlgorithm more thread efficient
requested to merge ATLAS-EGamma/athena:ATLASRECTS-6316_PFNeutralFlowElementCreatorAlgorithm into master
The issue is described at ATLASRECTS-6316, ATEAM-742 recreating accessors leads to a bit excessive locking.
This is close to what @akraszna suggested in ATLASRECTS-6316. A bit "tedious" but simple enough change.