[Durable-ownership] Maintainer is not in the exec-sponsor chain

Hello,
[As part of our further enhancement for durable ownership](https://github.com/github/fundamentals/discussions/1212), on December 10th we will begin to require all maintainers to be in the exec_sponsors organization.

We have found that this service will fail this requirement, and would like to ask it to be resolved beforehand.
Please make sure to fix it here: https://github.com/github/ownership/blob/main/github/github/open-source/ownership.yaml#L756
@adamsc64 @jakuboleksy

Start with ownership.yaml at the referenced line and review the service's maintainer entry against the exec_sponsors organization requirement described in the issue. Done means the service satisfies that requirement before the stated deadline; verify the ownership entry after the change.

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