message: Disable building CUDA and HIP for external build.
  When testing Ginkgo as an external for the subdir and export build
  tests, there should be no need to build CUDA and HIP as well since these
  tests only check the usability from a standard C++ executable.
diff: @@ -730,12 +730,10 @@ no-circular-deps:
  subdir-build:
  <<: *default_build
  stage: code_quality
  - image: localhost:5000/gko-cuda101-gnu8-llvm7-intel2019
  + image: localhost:5000/gko-nocuda-gnu9-llvm8
  variables:
  <<: *default_variables
  BUILD_OMP: "ON"
  - BUILD_CUDA: "ON"
  - BUILD_HIP: "ON"
  CI_PROJECT_PATH_SUFFIX: "/test_subdir"
  only:
  variables:
  @@ -744,19 +742,16 @@ subdir-build:
  allow_failure: no
  tags:
  - private_ci
  - - cuda
  - - gpu
  + - cpu
  # Ensure Ginkgo can be used when exporting the build directory
  export-build:
  <<: *default_build
  stage: code_quality
  - image: localhost:5000/gko-cuda102-gnu8-llvm8-intel2019
  + image: localhost:5000/gko-nocuda-gnu9-llvm8
  variables:
  <<: *default_variables
  BUILD_OMP: "ON"
  - BUILD_CUDA: "ON"
  - BUILD_HIP: "ON"
  EXPORT_BUILD_DIR: "ON"
  only:
  variables:
  @@ -765,9 +760,7 @@ export-build:
  allow_failure: no
  tags:
  - private_ci
  - - cuda
  - - gpu
  -
  + - cpu
  # Run clang-tidy and iwyu
  clang-tidy:
  