Merge branch 'test.G4AtlasTests-20181017' into 'master'

G4AtlasTests: Adjust ParticleGun test for change in default SG key name.

See merge request atlas/athena!15104

Simulation/G4Atlas/G4AtlasTests/share/test_AtlasG4_ParticleGun_electrons.py

@@ -101,6 +101,7 @@ job.G4TestAlg.SimTestTools += [CfgGetter.getPrivateTool("HECHitsTestTool", check
 from G4AtlasAlg.G4AtlasAlgConf import G4AtlasAlg
 g4AtlasAlg = G4AtlasAlg()
 g4AtlasAlg.RandomGenerator = "athena"
+g4AtlasAlg.InputTruthCollection='GEN_EVENT'
 from AthenaCommon.AppMgr import ServiceMgr
 from AthenaServices.AthenaServicesConf import AtRndmGenSvc
 atRndmGenSvc = AtRndmGenSvc()