Remove redundant HGTD namespaces

This MR touches many files, but the changes can be summarised as the removal of 3 namespaces for HGTD which are all redundant due to HGTD already appearing in the names in question: HGTDet was being used for HGTD tracking geometry, HGTDGeo for the HGTD detector factory, and HGTD for the HGTD clusters. Equivalent removal of namespaces also to follow soon in 21.9.

Tagging @tadej @aleopold @cohm @tawang

changed the description

build area is cleaned as the previous build was for the MR labeled as full-build

This merge request affects 8 packages:

• HighGranularityTimingDetector/HGTD_Conditions/HGTD_ConditionsAlgorithms
• HighGranularityTimingDetector/HGTD_DetDescr/HGTD_GeoModel
• HighGranularityTimingDetector/HGTD_Digitization/HGTD_FastDigitization
• HighGranularityTimingDetector/HGTD_EventCnv/HGTD_EventAthenaPool
• HighGranularityTimingDetector/HGTD_EventCnv/HGTD_EventTPCnv
• HighGranularityTimingDetector/HGTD_Reconstruction/HGTD_RecEvent/HGTD_PrepRawData
• HighGranularityTimingDetector/HGTD_Reconstruction/HGTD_TrackingGeometry
• Tracking/TrkConditions/TrackingGeometryCondAlg

Affected files list will not be printed in this case

Adding @jchapman ,@goetz ,@amorley ,@dshope ,@cohm ,@lshan as watchers

added Digitization HGTD Tracking master review-pending-level-1 labels

CI Result SUCCESS (hash e607991e)

	Athena	AthSimulation	AthGeneration	AnalysisBase	AthAnalysis	DetCommon
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
Athena: number of compilation errors 0, warnings 2
AthSimulation: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
AnalysisBase: number of compilation errors 0, warnings 5
AthAnalysis: number of compilation errors 0, warnings 0
DetCommon: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 41927]

Warnings are unrelated https://its.cern.ch/jira/browse/ATLINFR-4309. Approved

Sergei L1

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

merged

mentioned in commit 1bfc46c8

added sweep:ignore label

mentioned in merge request !48113 (merged)