Remove redundant and harmful using DetDesc::DetectorElement statements

gcc seemed fine with them but clang complains as this conflict with the declarations in DetectorElement.h

added RTA label

added lhcb-dd4hep label

we can only test this in the lhcb-dd4hep slot, no need for ci-test

• [2022-04-15 00:05] Validation started with lhcb-dd4hep#1096

mentioned in issue Moore#421 (closed)

approved this merge request

merged

mentioned in commit 745041c0

added cleanup label

mentioned in issue Moore#426 (closed)