Fix ingressClassName nesting in Refinery chart

Fixes honeycombio#422

Nest `ingressClassName` under `ingress` in the Refinery chart.

* Move `ingressClassName` under the `ingress` key in `charts/refinery/templates/ingress.yaml`
* Update the indentation to match the new structure
* Modify the condition to check for `ingress.ingressClassName` instead of `ingressClassName`

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For more details, open the [Copilot Workspace session](https://copilot-workspace.githubnext.com/honeycombio/helm-charts/issues/422?shareId=XXXX-XXXX-XXXX-XXXX).

charts/refinery/templates/ingress.yaml

@@ -25,8 +25,8 @@ spec:
       secretName: {{ .secretName }}
     {{- end }}
   {{- end }}
-  {{- if .Values.ingressClassName }}
-  ingressClassName: {{ .Values.ingressClassName }}
+  {{- if .Values.ingress.ingressClassName }}
+  ingressClassName: {{ .Values.ingress.ingressClassName }}
   {{- end }}
   rules:
     {{- range .Values.ingress.hosts }}