Pass GITLAB_REF_SLUG to CNG triggered pipelines

Signed-off-by: Rémy Coutable <remy@rymai.me>

scripts/trigger-build

@@ -68,6 +68,7 @@ module Trigger
 
     def base_variables
       {
+        'GITLAB_REF_SLUG' => ref_slug,
         'TRIGGERED_USER' => ENV['TRIGGERED_USER'] || ENV['GITLAB_USER_NAME'],
         'TRIGGER_SOURCE' => ENV['CI_JOB_URL'],
         'TOP_UPSTREAM_SOURCE_PROJECT' => ENV['CI_PROJECT_PATH'],
@@ -76,6 +77,12 @@ module Trigger
       }
     end
 
+    def ref_slug
+      return 'master' if ENV['CI_COMMIT_REF_SLUG'] =~ %r{(\Aqa[/-]|-qa\z)}
+
+      ENV['CI_COMMIT_REF_SLUG']
+    end
+
     # Read version files from all components
     def version_file_variables
       Dir.glob("*_VERSION").each_with_object({}) do |version_file, params|
@@ -106,18 +113,11 @@ module Trigger
     def extra_variables
       {
         'GITLAB_VERSION' => ENV['CI_COMMIT_SHA'],
-        'GITLAB_REF_SLUG' => ref_slug,
         'ALTERNATIVE_SOURCES' => 'true',
         'ee' => Trigger.ee? ? 'true' : 'false',
         'QA_BRANCH' => ENV['QA_BRANCH'] || 'master'
       }
     end
-
-    def ref_slug
-      return 'master' if ENV['CI_COMMIT_REF_SLUG'] =~ %r{(\Aqa[/-]|-qa\z)}
-
-      ENV['CI_COMMIT_REF_SLUG']
-    end
   end
 
   class CNG < Base