Tests fail on DD4HEP platforms

Since the change of default (?) 10 tests fail on x86_64_v2-centos7-gcc11-opt and alike with

ServiceManager                        ERROR Unable to initialize service "LHCb::Det::LbDD4hep::DD4hepSvc"

I tried to switch them off in qmt, but there's no such file. Everything is run from cmake. How do I veto platforms there? Or is there an easy (and desirable) fix to avoid the problem?

After !38 (merged) the tests now fail because the UT geometry is not implemented. I think the failing tests should still be vetoed on the relevant platforms.