[FEAT]: Authenticate as app with custom JWT token

[revblock]

Describe the need

I want to be able to create an App instance using a custom JWT token rather than having to pass in a private key.

My use case is that my private key is stored in a KMS so I don't have direct access to it. This means that I need to create the JWT and sign it there, I can then use it with octokit.

I think I'll be able to get around this manually but it would be nice if octokit handled this scenario.

Thanks

SDK Version

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API Version

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Relevant log output

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Code of Conduct

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[github-actions]

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[gr2m]

JWTs are very short lived, app.js relies on being able to create one as needed for it to function.

What do you need to use the JWT for? You can just use https://github.com/octokit/core.js or https://github.com/octokit/request.js and set the JWT as auth: JWT or headers: {authorization: `bearer ${JWT }` respectively