Trigger/TrigAlgorithms: Package cleanup

Cleanup of several packages under Trigger/TrigAlgorithms:

• cleanup cmake configuration
• enable flake8
• delete obsolete job options
• remove CLHEP dependency where applicable

added 63 commits

• 6753f234...f3dd4505 - 51 commits from branch atlas:master
• 2831508a - TrigFastTrackFinder: Cleanup CMake, enable flake8
• 648b466a - TrigT2BeamSpot: CMake cleanup
• 5ec6b4cf - TrigTauRec: CMake and package cleanup
• 6e6e2769 - TrigL2MissingET: Package cleanup
• 45fe08c6 - TrigMissingETMuon: Package cleanup
• 851ae44f - TrigTRTHighTHitCounter: Package cleanup
• e04a50d6 - TrigPartialEventBuilding: CMake cleanup, enable flake8
• e4c7bef6 - TrigTileMuId: CMake cleanup, enable flake8
• a87c8931 - TrigL2LongLivedParticles: Package cleanup
• fee32111 - TrigMinBias: CMake cleanup, enable flake8
• b7fe041d - TrigT2MinBias: CMake cleanup, enable flake8
• dd55c014 - TrigT2HistoPrmVtx: Package cleanup

Compare with previous version

This merge request affects 12 packages:

• Trigger/TrigAlgorithms/TrigFastTrackFinder
• Trigger/TrigAlgorithms/TrigL2LongLivedParticles
• Trigger/TrigAlgorithms/TrigL2MissingET
• Trigger/TrigAlgorithms/TrigMinBias
• Trigger/TrigAlgorithms/TrigMissingETMuon
• Trigger/TrigAlgorithms/TrigPartialEventBuilding
• Trigger/TrigAlgorithms/TrigT2BeamSpot
• Trigger/TrigAlgorithms/TrigT2HistoPrmVtx
• Trigger/TrigAlgorithms/TrigT2MinBias
• Trigger/TrigAlgorithms/TrigTRTHighTHitCounter
• Trigger/TrigAlgorithms/TrigTauRec
• Trigger/TrigAlgorithms/TrigTileMuId

Adding @cgrefe ,@calfayan ,@xiaozhon ,@adbailey ,@martindl ,@nagano ,@carquin ,@mvozak ,@rbielski ,@bernius as watchers

added JetEtmiss Tau Trigger master review-pending-level-1 labels

CI Result SUCCESS (hash dd55c014)

	Athena	AthSimulation	AnalysisBase	AthGeneration
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
Athena: number of compilation errors 0, warnings 6
AthSimulation: number of compilation errors 0, warnings 0
AnalysisBase: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 16743]

Unrelated build warnings.

The changes look good to me, and CI passes. Approving. (warnings are not related)

Xiaozhong (L1)

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

merged

mentioned in commit 360cc764

added sweep:ignore label