Fix reference to MakeNullPointer to work with root 6.22.00.

InDetVKalVxInJetTool package cleaning

See merge request atlas/athena!35984

Muon Detector Manager speed up

See merge request atlas/athena!36309

run offline an truth analyses from the same job using the new config files

See merge request atlas/athena!36304

remove the rest of RegSelSvc in MS

See merge request atlas/athena!36301

Syntax adjustments for root 6.22

See merge request atlas/athena!35630

AthenaCommon: Migrate python code to IOptionsSvc

See merge request atlas/athena!36289

Adding Calorimeter isolation to photon triggers

See merge request atlas/athena!36260

22.0-bug_fix-PixelRawDataByteStreamCnv

See merge request atlas/athena!36259

FlowElement inherits from IParticle, let the relevant DataVector know about it

See merge request atlas/athena!36296

Place DATAVECTOR_BASE at end of Jet_v1.h, similar to rel 21.2

See merge request atlas/athena!36298

TriggerMenuMT: Align PEB steps

Closes ATR-22012

See merge request atlas/athena!36295

Formulate BetheHeitler effects as separate interface and have a cache specific to what it fills

See merge request atlas/athena!36302

Sweeping !36140 from 21.0 to master.
Reverting the temporary special reference for HLTtau and restoring default trigger references

See merge request atlas/athena!36303

CxxUtils: Add missing test reference file.

See merge request atlas/athena!36283

Updating configuration to the MergedPixelsTool interface (ATLASRECTS-5652)

See merge request atlas/athena!36270

SGTools: Add missing test reference file.

See merge request atlas/athena!36285

TrigCostMonitorMT: Fix library building.

See merge request atlas/athena!36286

MagFieldUtils: Fix compilation with gcc10.

See merge request atlas/athena!36288

AthenaMonitoring: Migrate to IOptionsSvc

See merge request atlas/athena!36281

TrigInDetValidation - fix typo in chains for muon comparitor

See merge request atlas/athena!36314

CoraCool: Enable thread-safety checker.

See merge request atlas/athena!36305

L1CaloFEXSim: Fix clang warnings.

See merge request atlas/athena!36306

IsolationTool: Fix clang warning.

See merge request atlas/athena!36307

EventTagAlgs: python 3 fixes

See merge request atlas/athena!36308

(cherry picked from commit 96990a533f18666a29b74449ec67ab4e004b8a9f)

	modified:   Trigger/TrigValidation/TrigInDetValidation/share/comparitor.json

print statement -> function

Unused private data member.

Missing override keywords.
Unused private data members.

Enable thread-safety checker and fix identified issues.