Fix cluster-autoscaler chart to match with the examples

[foriequal0]

Partially resolves: #3724

Following lint error is well known issue:

templates/: template: cluster-autoscaler/templates/role.yaml:15:7: executing "cluster-autoscaler/templates/role.yaml" at <eq (default .Values.extraArgs.expander "") "priority">: error calling eq: invalid type for comparison

helm/helm#6376
The workaround doesn't seem to work.

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[foriequal0]

I've overlooked #3692 that it would solve the issue, but it wasn't enough. I should've read the code carefully and commented to it.

[gjtempleton]

I've had a play around with the code, and I think the issue you're seeing boils down to this: helm/helm#7091

The current default is an empty string, which YAML is then viewing as an unquoted nil.

I think there's a couple of options here:

1. We pipe the default to quote, i.e. {{- if eq (default .Values.extraArgs.expander "" | quote ) "priority" }}
2. We set the default to a dummy string/other expander, but don't set a default for the values in the values file.
3. We set a default value of expander: in the top level values

[gjtempleton]

/assign

[foriequal0]

Oh. I've mistakenly swapped default's argument. default takes a default value as a first argument. Swapping two arguments fixes that. I'll rebase and fix that.

[foriequal0]

@gjtempleton Can you review the fix?

[gjtempleton]

Sorry for the delay, thanks for fixing that!

/lgtm
/approve

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This pull-request has been approved by: foriequal0, gjtempleton

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