⚙️ Fixes an issue with proxy support for users that run self-hosted behind a proxy.

What's Changed

• fix: update proxy support to follow octokit change to fetch api by @peter-evans in https://github.com/peter-evans/create-pull-request/pull/2867

Full Changelog: https://github.com/peter-evans/create-pull-request/compare/v6.0.4...v6.0.5