Add a CovarianceHelper header and relevant tests

Add a CovarianceHelper header and relevant tests . Moving the covariance related code there.

Add comments and more checks to the new header and expand the tests to cover some interesting cases.

For now the clients stay to what they were using before. But hopefully the comments the additional helpers and the concrete examples explain the pros and cons.

ping @sroe, @nstyles @jcatmore @jchapman @jdandoy

This merge request affects 12 packages:

• Event/EventPrimitives
• InnerDetector/InDetMonitoring/TRTMonitoringRun3
• MuonSpectrometer/MuonReconstruction/MuonRecTools/MuonTGRecTools
• MuonSpectrometer/MuonReconstruction/MuonTrackMakers/MuonTrackMakerTools/MuonTrackFinderTools
• MuonSpectrometer/MuonReconstruction/MuonTrackMakers/MuonTrackMakerTools/MuonTrackSteeringTools
• MuonSpectrometer/MuonTruthAlgs
• Reconstruction/MuonIdentification/MuidTrackBuilder
• Reconstruction/MuonIdentification/MuonCombinedBaseTools
• Tracking/TrkExtrapolation/TrkExSTEP_Propagator
• Tracking/TrkFitter/TrkiPatFitter
• Tracking/TrkFitter/TrkiPatFitterUtils
• Tracking/TrkTools/TrkMaterialProvider

Affected files list will not be printed in this case

Adding @jojungge ,@stavrop ,@apsallid ,@gemmeren ,@pop ,@pscholer ,@goetz ,@sroe ,@cgrefe ,@rosati ,@rbianchi ,@gavrilen ,@kluit ,@calfayan as watchers

added DQ EDM InnerDetector MuonSpectrometer Reconstruction Tracking analysis-review-required main review-pending-level-1 labels

WARNING: big files (>100K) are found in the changeset

164K in file Reconstruction/MuonIdentification/MuidTrackBuilder/src/CombinedMuonTrackBuilder.cxx

120K in file Tracking/TrkExtrapolation/TrkExSTEP_Propagator/src/STEP_Propagator.cxx

CI Result SUCCESS (hash d80a7f97)

	Athena	AthSimulation	AthGeneration	AnalysisBase	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
AnalysisBase: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 2949]

changed the description

changed the description

added analysis-review-approved label and removed analysis-review-required label

added review-approved label and removed review-pending-level-1 label

mentioned in commit 69755213

merged