TrackRecord+TrkValHistUtils+EventBookkeeperMetaData: Fix cppcheck 2.14 warnings.

Prefer returning const references to members rather than copies.

This merge request affects 3 packages:

• Event/EventBookkeeperMetaData
• Simulation/G4Sim/TrackRecord
• Tracking/TrkValidation/TrkValHistUtils

Affected files list will not be printed in this case

Adding @gemmeren ,@jchapman as watchers

added EDM PhysValidation Simulation Tracking main review-pending-level-1 labels

CI Result SUCCESS (hash 929f5290)

	Athena	AthSimulation	AthGeneration	AthAnalysis
externals
cmake
make
tests

Full details available on this CI monitor view. Check the JIRA CI status board for known problems
Athena: number of compilation errors 0, warnings 0
AthSimulation: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 14167] (remote access info)

removed review-pending-level-1 label

added review-approved label

merged

mentioned in commit e22bac07