Helm chart - replicas value missing from gitaly configuration

Summary

We've installed gitlab-ee utilizing the official Helm chart. We noticed that there is only a single instance of gitaly running by default. We'd like a few replicas for purposes of redundancy. There is no Helm 'value' which will update the replicas setting in the stateful-set. I tried doing this manually.

kubectl edit statefulsets gitlab-gitaly

Setting the replicas field to 2.

The result is a failed pod with the following output.

+ /scripts/set-config /etc/gitaly/templates /etc/gitaly
Begin parsing .erb files from /etc/gitaly/templates
Writing /etc/gitaly/shell-config.yml
Writing /etc/gitaly/config.toml
(erb):14:in `<main>': Storage for node 1 is not present in the storageNames array. Did you use kubectl to scale up ? You need to solely use helm for this purpose (Exception)
	from /usr/lib/ruby/2.4.0/erb.rb:896:in `eval'
	from /usr/lib/ruby/2.4.0/erb.rb:896:in `result'
	from /scripts/set-config:22:in `block in <main>'
	from /scripts/set-config:18:in `each'
	from /scripts/set-config:18:in `<main>'

The instructions are to use Helm, but the setting is hard-coded.

Chart Version: gitlab-1.0.2