Adding new sleep task

[pmahindrakar-oss]

Why are the changes needed?

We need a lightweight in-process sleep task for leaseworker stress testing that does not rely on global plugin config or create task pods.

What changes were proposed in this pull request?

This PR adds a new core task plugin, core-sleep, which:

• takes one typed Duration input
• stays Running until the duration elapses
• completes on reconcile once elapsed
• keeps per-task start time in memory
• clears state on finalize

It also returns a user failure for invalid or missing duration input.

How was this patch tested?

Added unit tests for:

• immediate success for zero duration
• running-to-success behavior after elapsed time
• invalid input handling

Tested with:

go test ./flyteplugins/go/tasks/plugins/core/sleep

Labels

• added

Setup process

N/A

Screenshots

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Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Related PRs

• Related SDK PR for core-sleep

Docs link

N/A

• main
  • Flyte 2 #6583
    • Adding new sleep task 👈