GitHub integration is not working when proxy and no_proxy are configured

Summary

GitHub integration is not working when proxy and no_proxy are configured. It seems that the issue is caused by Faraday and not GitLab directly.

Steps to reproduce

p = Project.find_by_full_path("path/to/project)
u = User.find_by_username("username")

github = p.services.find_by_type("GithubService")

pp github, github.attributes

result = ::Integrations::Test::ProjectService.new(github, u, 'pipeline').execute

pp result

gitlab_rails['env'] = {
  "http_proxy" => "http://proxy.tld",
  "https_proxy" => "http://proxy.tld",
  "no_proxy" => "localhost,127.0.0.0/8,10.0.0.0/8,169.0.0.0/8,172.16.0.0/12,.local,.github.com,github.com"
}

What is the expected correct behavior

GitHub integration is supposed to work.

Relevant logs and/or screenshots

<Faraday::ConnectionFailed wrapped=#<Net::HTTPFatalError: 503 "Service Unavailable"