NodeSelector value is mangled when passed from YAML to ConfigMap

[dasantonym]

If I init my Helm Chart install using:

  nodeSelector:
    - {"node-role.kubernetes.io/worker": "worker"}

Then the value comes out as [map[node-role.kubernetes.io/worker:worker]] and the image puller errors because that's not valid JSON. If I then alter the ConfigMap to use {"node-role.kubernetes.io/worker": "worker"}, it works normally again.

Am I setting the value the wrong way? It doesn't seem to let me pass in the selector as a string value.