kube-apiserver: fix rendering auth header
Without this patch, the template content looks like following
(please note extra newline at the beginning):
```
...
```
So when you inject it into the YAML, it looks like:
```yaml
foo: "
..."
```
Instead of:
```yaml
foo: "..."
```
{{- define "token" -}}
{{ include (print $.Template.BasePath "/kube-apiserver-secret.yaml") . | sha256sum }}
{{- end -}}
-{{- define "authHeader" }}
+{{- define "authHeader" -}}
Bearer {{ template "token" . }}
{{- end }}
apiVersion: apps/v1
