Helm upgrade --install 相同docker image tag 更新pods
解决方法：
增加date: "{{ now | unixEpoch }}"
成果：
可以先本地debug看看更新：helm upgrade --install --dry-run --debug xxxx
然后执行：
helm upgrade --install xxx
参考：https://kubernetes.io/docs/concepts/containers/images/#updating-images
https://stackoverflow.com/questions/53450759/helm-upgrade-install-isnt-picking-up-new-changes?noredirect=1&lq=1
https://stackoverflow.com/questions/46336852/helm-upgrade-doesnt-pull-new-container
https://v3.helm.sh/docs/howto/charts_tips_and_tricks/#automatically-roll-deployments
