[FEAT]: export GraphqlResponseError from @octokit/graphql

[wolfy1339]

Describe the need

The class was exported in octokit/graphql.js#312 and it wasn't exported in the consuming packages upstream

See octokit/plugin-request-log.js#392 (comment)

SDK Version

octokit 4.0.2

API Version

N/A

Relevant log output

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[github-actions]

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