UPGRADE FAILED chart after 0.25.1 when tstune is enabled

[zfy0701]

What happened? after I upgrade to newest helm chart, it reports

  Error: UPGRADE FAILED: template: timescaledb-single/templates/statefulset-timescaledb.yaml:35:65: executing "timescaledb-single/templates/statefulset-timescaledb.yaml" at <sha256sum>: wrong type for value; expected string; got map[string]interface {}

looks like: https://github.com/timescale/helm-charts/commit/3804664b7bc14886db909809b5d83b65383d109a#diff-3210395104e9712528afa7119350e6250761db18b886c36af3e1dc600733fcfaR35

it can't be a map

in other place, we always first convert to string https://github.com/timescale/helm-charts/blob/d573ecf41b5ce1fe75e1ea431f7bf92c81722d80/charts/promscale/templates/deployment-promscale.yaml#L25

Did you expect to see something different? should not report error

How to reproduce it (as minimally and precisely as possible): start tsdb with default parameter

Environment

• Which helm chart and what version are you using?

• What is in your values.yaml ?

• Kubernetes version information:

  kubectl version

• Kubernetes cluster kind:

  insert how you created your cluster: kops, bootkube, etc.

Anything else we need to know?:

[paulfantom]

Fixed in #537