Fix/proxy auth

[jxlil]

Now RequestParser does not handle proxy authentication, this is to be able to use custom authentications:

yield Request(
            url=f"http://example.com",
            headers={
                "Proxy-Authorization": "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VyX2lkIiwiZXhwIjowMDAwMDAwMDAwfQ.8ZLkrPvu9-hKLnq8fghbZYdv-a-KMJfHtSndfFmT3PQ",
            },
            meta={
                "impersonate": "chrome110",
                "proxy": "http://0.0.0.0:80000",
            },
        )

yield Request(
            url=f"http://example.com",
            meta={
                "impersonate": "chrome110",
                "proxy": "http://0.0.0.0:80000",
                "impersonate_args": {
                    "proxy_auth": ("user", "passw"),
                },
            },
        )

Closes #13