[Backport 6.53.x] Rotate e2e tests API key

[agent-platform-auto-pr]

Backport 88c98ae from #31818.

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What does this PR do?

Rotate e2e tests API key

Motivation

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Possible Drawbacks / Trade-offs

Additional Notes

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[pr-commenter]

Test changes on VM

Use this command from test-infra-definitions to manually test this PR changes on a VM:

inv create-vm --pipeline-id=50530879 --os-family=ubuntu