...
spec:
  ...
  template:
    ...
    spec:
      containers:
        ...
        volumeMounts:
        - mountPath: /var/run/secrets/tokens
           name: sa-token
      ...
      volumes:
      - name: sa-token
        projected:
          defaultMode: 420
          sources:
          - serviceAccountToken:
              audience: iam
              expirationSeconds: 3600
              path: sa-token
...
