CI: Change pipeline name for scheduled pipeline

This description is already displayed on the web UI of the list of
pipeline, but using it as "name" will make it available in webhooks as
well and can be used by a bot.

This doesn't change the behavior for other pipeline types, where the
variable isn't set.

Signed-off-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>

.gitlab-ci.yml

@@ -4,6 +4,7 @@ variables:
     description: "Regex to select only some jobs, must be enclosed with /. For example /job1|job2/"
 
 workflow:
+  name: "$CI_PIPELINE_SCHEDULE_DESCRIPTION"
   rules:
     - if: $CI_COMMIT_BRANCH =~ /^(master|smoke|^coverity-tested\/.*|stable-.*)$/
       when: never