Adapt MicroDSTConf to change in L0 decoder
A new implementation of the L0 decoder, called L0DUDecoder instead of L0DUFromRawAlg, was added in LHCb!627 (merged).
This merge request adapts MicroDSTConf/TriggerConfUtils.py
to this change as otherwise the configuration crashes because two algorithms configure the same data-on-demand location.