--signed is not v0.21

.gitlab-ci.yml

@@ -121,7 +121,11 @@ spack:install_compilers:
       --use-cache
       ${COMPILER_LIST_SPECS}
 
-    - /spack/spack/bin/spack buildcache create --update-index --signed /buildcache ${COMPILER_LIST_SPECS}
+    - /spack/spack/bin/spack buildcache create
+      --update-index
+      --key EDC904DCE3D2E84E
+      /buildcache ${COMPILER_LIST_SPECS}
+
     - |
       echo 'definitions: [ compilers: [' ${COMPILER_LIST_SPECS} ']]' > compiler_definitions.yaml