Remove NODE_TLS_REJECT_UNAUTHORIZED

[nabuskey]

We currently use NODE_TLS_REJECT_UNAUTHORIZED in the ref impl here:

stacks/ref-implementation/backstage/manifests/install.yaml

Line 257 in 2b12c4d

- name: NODE_TLS_REJECT_UNAUTHORIZED

We should remove that and trust the cert idpbuilder issues instead. i.e.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: backstage
  namespace: backstage
spec:
    spec:
      containers:
        - command:
            - node
            - packages/backend
            - --config
            - config/app-config.yaml
          env:
            - name: LOG_LEVEL
              value: debug
            - name: NODE_EXTRA_CA_CERTS
              value: "/app/config/ca.crt"
          envFrom:
            - secretRef:
                name: backstage-env-vars
            - secretRef:
                name: gitea-credentials
            - secretRef:
                name: argocd-credentials
          image: ghcr.io/cnoe-io/backstage-app:135c0cb26f3e004a27a11edb6a4779035aff9805
          name: backstage
          ports:
            - containerPort: 7007
              name: http
          volumeMounts:
            - mountPath: /app/config
              name: backstage-config
              readOnly: true
      serviceAccountName: backstage
      volumes:
        - name: backstage-config
          projected:
            sources:
              - secret:
                  name: idpbuilder-cert
                  items:
                    - key: ca.crt
                      path: ca.crt
              - configMap:
                  items:
                    - key: app-config.yaml
                      path: app-config.yaml
                  name: backstage-config
              - secret:
                  items:
                    - key: k8s-config.yaml
                      path: k8s-config.yaml
                  name: k8s-config