**Description**

Make HttpSensor `headers` parameter templated.

**Use case / motivation**

This would allow for passing data from other tasks, such as an API token, in the headers.

**Related Issues**

N/A
airflow/providers/http/sensors/http.py
self,
        *,
        endpoint: str,
        http_conn_id: str = 'http_default',
        method: str = 'GET',
        request_params: Optional[Dict[str, Any]] = None,
        headers: Optional[Dict[str, Any]] = None,
        response_check: Optional[Callable[..., bool]] = None,
        extra_options: Optional[Dict[str, Any]] = None,
        **kwargs: Any,
    ) -> None:
        super().__init__(**kwargs)
        self.endpoint = endpoint
        self.http_conn_id = http_conn_id
        self.request_params = request_params or {}
        self.headers = headers or {}
        self.extra_options = extra_options or {}
        self.response_check = response_check
        self.hook = HttpHook(method=method, http_conn_id=http_conn_id)
    def poke(self, context: Dict[Any, Any]) -> bool: