fix(deps): update dependency @octokit/rest to v21

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@octokit/rest	^20.0.2 -> ^21.0.0

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Release Notes

octokit/rest.js (@​octokit/rest)

### [`v21.0.0`](https://togithub.com/octokit/rest.js/compare/v20.1.1...12b6c6521dc767a8c127fbbfcc74b0c76d1ab056) [Compare Source](https://togithub.com/octokit/rest.js/compare/v20.1.1...v21.0.0)

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