Using github webhook to trigger repo mirroring

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Problem to solve

I followed the instructions from the following link Using GitLab CI/CD with a GitHub repository | GitLab
BTW, the doc is not updated according to what described in Projects API | GitLab

The problem is that github doesn’t allow to set the header in their webhook config, how can I send pull mirroring request?

Steps to reproduce

Configuration

Versions

free service

Helpful resources

Thanks for taking the time to be thorough in your request, it really helps! :blush: