fix multiline strings

[filipecaixeta]

Zookeeper has a yaml zookeeper-metadata.yaml that contains multiline string fields.
You will see something like this in that file

args:
  - >
    bin/pulsar initialize-cluster-metadata \

The problem with this is that the main library in Go for parsing yaml contains a bug and it is not able to generate the yaml files correctly.

I'm using Kustomize to deploy my helm charts (which uses that yaml library) and that is breaking the deployment.

Yaml also has another syntax for multiline string that works just fine

args:
  - |
    bin/pulsar initialize-cluster-metadata \

kafkaesque-io/pulsar-helm-chart#92

[michaeljmarshall]

LGTM. Thanks for your contribution @filipecaixeta.

The test failed for reasons unrelated to this PR. Instead of rebasing, I tested this on my local machine and verified that it works as expected.