Merge branch 'nrbffs/ci-cache-only-dl' into 'master'

CI: cache only downloads

See merge request firmware/site-ffs!3

.gitlab-ci.yml

@@ -26,9 +26,8 @@ stages:
     expire_in: 1 day
   cache:
     paths:
-      - gluon/packages
       - gluon/openwrt/dl
-    key: "$CI_COMMIT_TAG-$GLUON_TARGET"
+    key: "gluon-cache"
  
 target:ar71xx-generic:
   extends: .target