[Core feature] Plumb execution user identity to data plane

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Motivation: Why do you think this is important?

It would be useful for the Flyte data plane (ie. plugins) to know the identity of the user that triggered an execution for propagation into upstream systems.

Goal: What should the final outcome look like, ideally?

It would be nice if the user identity were accessible in the task execution context.

Describe alternatives you've considered

None

Propose: Link/Inline OR Additional context

No response

Are you sure this issue hasn't been raised already?

• Yes

Have you read the Code of Conduct?

• Yes