Change zookeeper helm chart dependency

[pedro93]

The current zookeeper helm chart component of Pinot's Kubernetes deployment is deprecated as of Nov 13, 2020.
Consider changing to the more up-to-date, better documented helm chart from bitnami: https://github.com/bitnami/charts/tree/master/bitnami/zookeeper

[ivanvy-wix]

The switch to Bitnami’s ZooKeeper chart was made in #7955 (chart v7.0.0, ZooKeeper v3.7.0). Later updated to v9.2.7 version of the chart (ZooKeeper v3.8.0) in #8936. I think the issue can be closed now.