AERAKI_IS_MASTER does not take effect

[tanjunchen]

Describe the bug
There is a bug for primary-remote architecture of istio if we use aeraki in it.

2023-06-09T09:55:00.259687Z warn The environment variable POD_NAME was registered multiple times using different metadata: {POD_NAME false false 0}, {POD_NAME Aeraki-1d13822c-eca8-470f-a828-57938547f5f2 false false 0} 2023-06-09T09:55:00.259743Z info Aeraki parameter: aeraki-xds-address: aeraki.istio-system

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