[ATR-26540] Downgrade missing L1 muon ROIs in MuonCluster to WARNING. Small tidy up of Hypo
Due to the noL1Sim tests, we are seeing evidence of CTPID missmatched in HLT seeding.
If the MuCluster algorithm runs in an event with not enough muon ROI it (rightly) complains, but it then also stops these jobs.
We should figure out what to do about the noL1sim jobs. But we can also downgrade this to a WARNING in the near term.
Also a quick refactor to the HypoAlg to link all L1 ROIs rather than just one. Behaviour should be unchanged.
cc @mischott