fix: add whatsapp cache key

.gitlab-ci.yml

@@ -150,6 +150,8 @@ send-release-notes-to-group:
     GIT_STRATEGY: none
     MUDSLIDE_CACHE_FOLDER: './mudslide_cache'
   cache:
+    key: whatsapp
+    paths:
       - mudslide_cache
   script:
     - mkdir -p mudslide_cache