Kube-Downscaler does not respect release namespace when templating

The `kube-downscaler` helm chart doesn't honor the namespace passed in to helm. This is because the chart is missing the typical metadata configuration on its kubernetes resources. ie, this problem is the same as this one for another chart: #216

To reproduce this problem:

```bash
helm fetch deliveryhero/kube-downscaler --version 0.7.4 --untar=true
helm template my-release kube-downscaler --namespace kube-systen  > kube-downscaler.yaml
```

The `deployment.yaml` and other files will have no namespace. ie, it is not configured here: https://github.com/deliveryhero/helm-charts/blob/0b420820e3f88d5e7f9f10ddd1c9a029adb9a422/stable/kube-downscaler/templates/deployment.yaml#L3

Fix is as below:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: "{{ $fullname }}-{{ .name }}"
  namespace: {{ .Release.Namespace }}
```

stable/kube-downscaler/templates/cronjob.yaml

@@ -3,6 +3,7 @@ apiVersion: {{ template "batch.apiVersion" . }}
 kind: CronJob
 metadata:
   name: {{ template "kube-downscaler.fullname" . }}-de-annotate
+  namespace: {{ .Release.Namespace }}
   labels:
 {{ include "kube-downscaler.labels" . | indent 4 }}
     {{- if .Values.extraLabels }}

stable/kube-downscaler/templates/deployment.yaml

@@ -2,6 +2,7 @@ apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: {{ template "kube-downscaler.fullname" . }}
+  namespace: {{ .Release.Namespace }}
   labels:
 {{ include "kube-downscaler.labels" . | indent 4 }}
     {{- if .Values.extraLabels }}

stable/kube-downscaler/templates/serviceaccount.yaml

@@ -6,4 +6,5 @@ metadata:
   labels:
 {{ include "kube-downscaler.labels" . | indent 4 }}
   name: {{ template "kube-downscaler.fullname" . }}
+  namespace: {{ .Release.Namespace }}
 {{- end -}}