Question: Spinnaker pipeline shows running even after all the tasks are completed. What can we do?

Answer: One possible solution is to clear the Redis Cache.

1) install Redis CLI [ Try: https://codewithhugo.com/install-just-redis-cli-on-ubuntu-debian-jessie/] 
2) execute " FLUSHALL " command to clear the cache. [ Try: https://www.cyberciti.biz/faq/how-to-flush-redis-cache-and-delete-everything-using-the-cli/]