feat(chart): make dind container template configurable

In addition to the pre-populated values for the dind container template
parse spec from Values.template.spec.containers["dind"] to enable users
to add config

charts/gha-runner-scale-set/templates/_helpers.tpl

@@ -96,6 +96,15 @@ volumeMounts:
 {{- end }}
 
 {{- define "gha-runner-scale-set.dind-container" -}}
+{{- range $i, $container := .Values.template.spec.containers }}
+  {{- if eq $container.name "dind" }}
+    {{- range $key, $val := $container }}
+      {{- if and (ne $key "env") (ne $key "volumeMounts") (ne $key "name") (ne $key "image") (ne $key "command") (ne $key "args") }}
+{{ $key }}: {{ $val | toYaml | nindent 2 }}
+      {{- end }}
+    {{- end }}
+  {{- end }}
+{{- end }}
 image: docker:dind
 args:
   - dockerd

charts/gha-runner-scale-set/tests/values_dind_merge_spec.yaml

@@ -22,10 +22,21 @@ template:
         limits:
           memory: "64Mi"
           cpu: "250m"
+        requests:
+          cpu: "32Mi"
+          memory: "100Mi"
+    - name: dind
+      resources:
+        limits:
+          memory: "64Mi"
+          cpu: "250m"
+        requests:
+          cpu: "32Mi"
+          memory: "100Mi"
     volumes:
     - name: work
       hostPath:
         path: /data
         type: Directory
 containerMode:
-  type: dind
+  type: dind