Merge topic 'ci-cuda'

f7af01efb6 gitlab-ci: add job testing cuda10.2 with clang 11
9548b059c0 ci: add clang-11 to cuda10.2 base image

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Ben Boeckel <ben.boeckel@kitware.com>
Merge-request: !6236