feat(Backend + SDK): Update kfp backend and kubernetes sdk to support node affinity

[cjidboon94]

Description of your changes: This PR adds support for node affinity to the driver and kubernetes_platform SDK.

It is a follow up to #10671 and #10583, which updated the protobuf and Golang stub.

It follows the excellent example set by https://github.com/kubeflow/pipelines/pull/10427.

Huge thanks to @Tomcli for paving the way and sharing how to validate things end to end. Part of https://github.com/kubeflow/pipelines/issues/9768 and https://github.com/kubeflow/pipelines/issues/9682

Pod (Anti)Affinity will be added in a separate PR

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