httpx upgrade Compatibility

[cnzyan]

core\request_engine.py should change from line #23:

Ensure User-Agent is set

 if "User-Agent" not in self.headers:
       self.headers["User-Agent"] = DEFAULT_USER_AGENT
  transport = httpx.AsyncHTTPTransport(proxy=self.proxies)
   self.client = httpx.AsyncClient(
      mounts={"all://": transport},
      headers=self.headers,
      cookies=self.cookies,
      timeout=self.timeout,
      verify=False, # Often needed for pentesting targets with self-signed certs
      trust_env=False # Ignore system proxies to avoid issues with localhost
   )