Allow Helm Chart deploy image from digest

GKE Binary Authorization only supports image pull by digest - [Ref](https://cloud.google.com/binary-authorization/docs/deploying-containers#deploy_the_container_image)
* if `.values.reloader.deployment.image.digest` is defined, pull image from digest
* otherwise pull image from tag

deployments/kubernetes/chart/reloader/templates/deployment.yaml

@@ -75,9 +75,13 @@ spec:
       containers:
       {{- if $.Values.global.imageRegistry }}
       - image: "{{ $.Values.global.imageRegistry }}/{{ .Values.reloader.deployment.image.base }}:{{ .Values.reloader.deployment.image.tag }}"
-{{- else }}
+      {{- else }}
+      {{- if .Values.reloader.deployment.image.digest }}
+      - image: "{{ .Values.reloader.deployment.image.name }}@{{ .Values.reloader.deployment.image.digest }}"
+      {{- else }}
       - image: "{{ .Values.reloader.deployment.image.name }}:{{ .Values.reloader.deployment.image.tag }}"
-{{- end }}
+      {{- end }}
+      {{- end }}
         imagePullPolicy: {{ .Values.reloader.deployment.image.pullPolicy }}
         name: {{ template "reloader-fullname" . }}
         env:

deployments/kubernetes/chart/reloader/values.yaml

@@ -99,6 +99,7 @@ reloader:
       name: ghcr.io/stakater/reloader
       base: stakater/reloader
       tag: v1.0.121
+      # digest: sha256:1234567
       pullPolicy: IfNotPresent
     # Support for extra environment variables.
     env: