[PWGDQ] Improvements tableReader_withAssoc and dqEfficiency_withAssoc, and simplifying FillPairVertexing

[mcoquet642]

• Same fix as in PR#17893 to enable best muon skimming when not using ML model
• tableReader_withAssoc : same-event-pairing : filling histograms only when fConfigQA is true
• dqEfficiency/tableReader_withAssoc : muon-selection : Removing unnecessary fetching of GRPMag from ccdb
• dqEfficiency/tableReader_withAssoc : same-event-pairing : Removing unnecessary fetching of geometry from ccdb
• dqEfficiency/tableReader_withAssoc : same-event-pairing : Removing deprecated option cfgCorrFullGeo
• dqEfficiency/tableReader_withAssoc : same-event-pairing : Removing manual setting of the magnetic field
• dqEfficiency/tableReader_withAssoc : same-event-pairing : muon vertexing is now enabled only for the process
  processMuonOnlyVertexingSkimmed. For other processes, vertexing is disabled
• VarManager/dqEfficiency/tableReader_withAssoc : removing fPropToPCA option, which should always be true
• VarManager : Simplifying the code for FillPairVertexing : removing unnecessary calculations and improving readability

[github-actions]

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