[feature request] Consider exposing node labels via downward api

[xvdy]

What would you like to be added:
Consider exposing node labels via downward api #40610

Why is this needed:
对于跨多个 az 的集群，pod 能够感知到目前自己在哪个 az，期望是将 az 信息通过环境变量暴露，kruise 是否有办法支持这样的能力？
对标这个 issue：kubernetes/kubernetes#40610

[zmberg]

@xvdy 这个能力Kruise 支持不了昂。你还是持续关注社区吧。

[furykerry]

maybe we could populate pod labels using node labels in podmarker

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.