meta-*: bump poky from fa7dd6d to a817e20 in the layers group

Bumps the layers group with 1 update: poky.


Updates `poky` from `fa7dd6d` to `a817e20`

---
updated-dependencies:
- dependency-name: poky
  dependency-version: a817e2016f3728bfcab9cad041620cc66d77e34b
  dependency-type: direct:production
  dependency-group: layers
...

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Author: dependabot[bot]