feat: add return types for request.parseSuccessResponseBody

[wolfy1339]

Resolves #606

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Before the change?

• The response types would always return the data as an object whether or not the request.parseSuccessResponseBody was set to false

After the change?

• The response types take into account the request.parseSuccessResponseBody, and set it to be ReadableStream

Pull request checklist

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)

Does this introduce a breaking change?

Please see our docs on breaking changes to help!

• Yes
• No

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[github-actions]

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[wolfy1339]

This fails the tests, but works in the code when the option is used.

There are some changes that need to be made to have this ready to ship

[wolfy1339]

The tests fail for the assertPaginate test

[wolfy1339]

@octokit/js If one of you could have a look and help this along. I would really appreciate the help on this one