Issue closing fails with HttpError

[Kagami Sascha Rosylight]

https://github.com/microsoft/TypeScript-DOM-lib-generator/runs/3450806601?check_suite_focus=true

Run OSS-Docs-Tools/code-owner-self-merge@1.6.0
Running version 1.6.0
Creating comments and closing
(node:1784) UnhandledPromiseRejectionWarning: HttpError: Not Found
    at /home/runner/work/_actions/OSS-Docs-Tools/code-owner-self-merge/1.6.0/node_modules/@octokit/request/dist-node/index.js:66:23
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
    at async Actor.closePROrIssueIfInCodeowners (/home/runner/work/_actions/OSS-Docs-Tools/code-owner-self-merge/1.6.0/index.js:208:5)
(node:1784) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:1784) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.