bug: Request headers when using fingerprint generator or header generator are not saved in `context.request.headers`

Request headers are correctly present when making the request, but context is not aware of them.
This is due to the fact that the request headers are set directly on Playwright in browserforge and this bypasses our common header setting approach

Make sure that regardless of how the headers are set, they are present in the context.request.headers

This is same situation as when setting headers through header generator - also missing in the context.