Allow use configmap and secret simultaneously

[makavity]

Since part of the data is a config, and part is a secret, I think it makes sense to add the ability to use a configmap together with a secret.
Something like this:
https://github.com/kellnr/helm/blob/baede8e40d96d174e7d4506a2bf44ebd120b04b6/charts/kellnr/templates/deployment.yaml#L106C1-L112C23

{{- if .Values.secret.enabled }}
- secretRef:
    name: {{ .Values.secret.name | quote }}
{{- end }}
{{- if .Values.configmap.enabled }}
- configMapRef:
    name: {{ .Values.configMap.name | quote }}
{{- end }}