feat: support confidential nodepools

[abhikaddy]

This fixes open issue #1386.

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[abhikaddy]

@apeabody Good Day! can I get a review?

[apeabody]

/gcbrun

[apeabody]

@apeabody Good Day! can I get a review?

Triggered the Integration tests

[abhikaddy]

@apeabody can I get access to build failure logs?

[apeabody]

/gcbrun

[abhikaddy]

Hi Good Day!
Can I get a merge? @apeabody @Jberlinsky @ericyz

[github-actions]

This PR is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[t-indumathy]

Can you also backport this change to v30.x pls, as this is a gap that ought to have been addressed from that version?

[apeabody]

Thanks for the contribution @abhikaddy!

Can you please rebase your change? Thanks!

[t-indumathy]

@abhikaddy Can you please rebase ?