Don't run stress tests for lock-async on JVM
Don't run stress tests for lock-async on JVM

Since fixing the ThreadPoolScheduler (commit 8d954027fd) these tests
are dying badly. I'm quite sure, an underlying problem is surfacing
now.

tbrowder/rakudo,tony-o/rakudo,lucasbuchala/rakudo,tony-o/rakudo,softmoth/rakudo,nbrown/rakudo,labster/rakudo,salortiz/rakudo,softmoth/rakudo,salortiz/rakudo,tbrowder/rakudo,labster/rakudo,rakudo/rakudo,nbrown/rakudo,tony-o/rakudo,nbrown/rakudo,labster/rakudo,softmoth/rakudo,lucasbuchala/rakudo,MasterDuke17/rakudo,Gnouc/rakudo,salortiz/rakudo,Gnouc/rakudo,lucasbuchala/rakudo,lucasbuchala/rakudo,salortiz/rakudo,MasterDuke17/rakudo,nbrown/rakudo,softmoth/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,labster/rakudo,tbrowder/rakudo,Gnouc/rakudo,tbrowder/rakudo,Gnouc/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,rakudo/rakudo,Gnouc/rakudo,softmoth/rakudo,tbrowder/rakudo,tony-o/rakudo,salortiz/rakudo,rakudo/rakudo,rakudo/rakudo,Gnouc/rakudo,rakudo/rakudo,labster/rakudo,tony-o/rakudo,nbrown/rakudo,MasterDuke17/rakudo,salortiz/rakudo,labster/rakudo,nbrown/rakudo,MasterDuke17/rakudo,tony-o/rakudo,rakudo/rakudo