remove simID and recID from the associations

simID was originally introduced in eicd as there was no way to refer to a
EDM4hep collection at the time
https://github.com/eic/EDM4eic/blame/7299aba54097a3f2a17c0242731c9dabe68fb450/eic_data.yaml#L546-L547
Later, recID was introduced for convenience, and possibly had to be used to
hack associations into an early versions of EICrecon.  We don't need neither.
This information is already available via sim and rec relations.

edm4eic.yaml

@@ -443,8 +443,6 @@ datatypes:
     Description: "Used to keep track of the correspondence between MC and reconstructed particles"
     Author: "S. Joosten"
     Members:
-      - uint32_t          simID             // Index of corresponding MCParticle (position in MCParticles array)
-      - uint32_t          recID             // Index of corresponding ReconstructedParticle (position in ReconstructedParticles array)
       - float             weight            // weight of this association
     OneToOneRelations :
       - edm4eic::ReconstructedParticle rec  // reference to the reconstructed particle
@@ -454,8 +452,6 @@ datatypes:
     Description: "Association between a Cluster and a MCParticle"
     Author : "S. Joosten"
     Members:
-      - uint32_t          simID             // Index of corresponding MCParticle (position in MCParticles array)
-      - uint32_t          recID             // Index of corresponding Cluster (position in Clusters array)
       - float             weight            // weight of this association
     OneToOneRelations:
       - edm4eic::Cluster  rec               // reference to the cluster
@@ -465,8 +461,6 @@ datatypes:
     Description: "Association between a Track and a MCParticle"
     Author : "S. Joosten"
     Members:
-      - uint32_t          simID             // Index of corresponding MCParticle (position in MCParticles array)
-      - uint32_t          recID             // Index of corresponding Track (position in Tracks array)
       - float             weight            // weight of this association
     OneToOneRelations:
       - edm4eic::Track    rec               // reference to the track
@@ -476,8 +470,6 @@ datatypes:
     Description: "Association between a Vertex and a MCParticle"
     Author : "S. Joosten"
     Members:
-      - uint32_t          simID             // Index of corresponding MCParticle (position in MCParticles array)
-      - uint32_t          recID             // Index of corresponding Vertex (position in Vertices array)
       - float             weight            // weight of this association
     OneToOneRelations:
       - edm4eic::Vertex     rec             // reference to the vertex