Fix build: replace unused @ts-expect-error with explicit type assertion

[Copilot]

CI "Tests" workflow fails at npm run build — ncc build rejects the @ts-expect-error on line 222 of repository.ts as unused (TS2578), even though tsc accepts it. Discrepancy between ts-loader (used by ncc) and tsc type resolution for the Octokit response type.

• Replace @ts-expect-error suppression with as unknown as string type assertion, which is explicit and works under both compilation pipelines

// before
// @ts-expect-error
return response.data;

// after
return response.data as unknown as string;

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.