* Make zookeeper healthchecks compatible with Alpine's busybox nc
* Test Pulsar 3.3.0 image
* Use 127.0.0.1 instead of localhost in zookeeper healthchecks
- Alpine nc fails if "localhost" is used.
- perhaps it defaults to use IPv6?
* Disable testing with Pulsar 3.3.0 image until 3.3.1 is released
- the image needs "apk add bind-tools" since busybox nslookup isn't compatible with kubernetes