gitlab-ci: improve condition of scheduled job

.gitlab-ci.yml

@@ -85,7 +85,7 @@ benchmark:
   stage: test
   tags: ['plafrim']
   rules:
-    - if: $CI_PIPELINE_SOURCE == "schedule"
+    - if: $CI_PIPELINE_SOURCE == "schedule" && $CI_PIPELINE_SCHEDULE_DESCRIPTION == "Benchmarks"
   needs: []
   variables:
     CI_HOSTNAME: zonda
@@ -109,7 +109,7 @@ database:
   stage: deploy
   tags: ['plafrim']
   rules:
-    - if: $CI_PIPELINE_SOURCE == "schedule"
+    - if: $CI_PIPELINE_SOURCE == "schedule" && $CI_PIPELINE_SCHEDULE_DESCRIPTION == "Benchmarks"
   needs: ['benchmark']
   script:
     - guix time-machine -C .guix/scalfmm-channels.scm -- shell --pure --preserve="^CI|proxy$"