Refactor MuonLRTOverlapRemovalTool

This MR tries to fix a bug pointed in https://its.cern.ch/jira/browse/ATLASMCP-186, where in the second strategy passThroughAndDecorate, the decoration MuonLRTOverlapDecision was being overwritten in every instance of the LRT loop. There were other problems such as the decor not being filled for prompt muons if the LRT container is empty. This should now be fixed since the decors are written in independent loop instances now.

Requesting a review from @goblirsc.