message: Spack config: fix deprecated yaml syntax
diff: @@ -188,9 +188,10 @@ packages:
  doxygen:
  version: [1.8.5]
  - paths:
  - doxygen: /usr/bin/doxygen
  buildable: False
  + externals:
  + - spec: doxygen@1.8.5
  + prefix: /usr/bin
  # GPU
  cuda:
  