change LCG layer to python3_ATLAS_8

change LCG layer to python3_ATLAS_8 This layer contains: new version of OpenLoops, Sherpa and H7 libs using the new OpenLoops version, Superchic4.02 MadGraph2.9.2 with a patch for MadSpin Sherpa compiled w/o libHepMC3rootIO

added full-build full-unit-tests labels

build area is cleaned as MR is labeled as full-build

This merge request affects 6 packages:

• Projects/AthAnalysis
• Projects/AthDataQuality
• Projects/AthGeneration
• Projects/AthSimulation
• Projects/Athena
• Projects/VP1Light

Affected files list will not be printed in this case

Adding @krumnack ,@jchapman ,@akraszna ,@rbianchi as watchers

added Build master review-pending-level-1 labels

CI Result SUCCESS (hash e915f486)

	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 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
DetCommon: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 30637]

Seems safe enough.

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

merged

mentioned in commit 58f8455a

added sweep:ignore label