No cluster associated to SplitPhotons

The renaming from "FutureNeutralProtoPAlg" to "NeutralProtoPAlg" revealed a bug. For SplitPhotons currently no Cluster is associated, or at least by use of the function https://gitlab.cern.ch/lhcb/LHCb/-/blob/master/CaloFuture/CaloFutureUtils/src/CaloFutureAlgUtils.cpp#L158

Consequences are essentially all info from https://gitlab.cern.ch/lhcb/Rec/-/blob/master/CaloFuture/CaloFutureTools/src/CaloFutureHypoEstimator.cpp#L137-228 for these objects turned into neutral ProtoParticles don't get filled.

The following discussion from !4426 (merged) should be addressed:

• @mveghel started a discussion: (+2 comments)

  After last check with @msaur on the reference updates, something weird was spotted with what should be an unrelated part, split photons (made with different algorithms) have no cluster associated anymore, this will have an effect on the NeutralPID of those objects, so we will have to understand this before merging

  Extra algos with Counters : NeutralProtoPAlg_773b88f8, NeutralProtoPAlg_ae11d719.CaloFu..., NeutralProtoPAlg_ae11d719, NeutralProtoPAlg_773b88f8.CaloFu...
    Counters for algo NeutralProtoPAlg_773b88f8
      (NeutralProtoPAlg_773b88f8 new) Neutral Protos | 89 | 10124 | 113.75 | 53.200 | 9.0000 | 215.00
      (NeutralProtoPAlg_773b88f8 new) Neutral Protos from MergedPi0s | 89 | 234 | 2.6292 | 2.5894 | 0.0000 | 11.000
      (NeutralProtoPAlg_773b88f8 new) Neutral Protos from Photons | 89 | 9422 | 105.87 | 47.319 | 9.0000 | 204.00
      (NeutralProtoPAlg_773b88f8 new) Neutral Protos from SplitPhotons | 89 | 468 | 5.2584 | 5.1789 | 0.0000 | 22.000
    Counters for algo NeutralProtoPAlg_ae11d719.CaloFu...
      (NeutralProtoPAlg_ae11d719.CaloFu... new) no cluster | 468 | 468 | 1.0000 | 0.0000 | 1.0000 | 1.0000
    Counters for algo NeutralProtoPAlg_ae11d719
      (NeutralProtoPAlg_ae11d719 new) Neutral Protos | 89 | 10098 | 113.46 | 52.924 | 9.0000 | 213.00
      (NeutralProtoPAlg_ae11d719 new) Neutral Protos from MergedPi0s | 89 | 234 | 2.6292 | 2.5894 | 0.0000 | 11.000
      (NeutralProtoPAlg_ae11d719 new) Neutral Protos from Photons | 89 | 9396 | 105.57 | 47.049 | 9.0000 | 204.00
      (NeutralProtoPAlg_ae11d719 new) Neutral Protos from SplitPhotons | 89 | 468 | 5.2584 | 5.1789 | 0.0000 | 22.000
    Counters for algo NeutralProtoPAlg_773b88f8.CaloFu...
      (NeutralProtoPAlg_773b88f8.CaloFu... new) no cluster | 468 | 468 | 1.0000 | 0.0000 | 1.0000 | 1.0000

  Look at the "no cluster" case