**What happened**:

With the new Backport providers, when calling `DataflowCreatePythonJobOperator` with an empty `py_rerquirments` Dataflow commands always launch inside a virtualenv.

**What you expected to happen**:

The Dataflow command should run locally.


airflow/providers/google/cloud/operators/dataflow.py
#
#
#
"""
This module contains Google Dataflow operators.
"""
import copy
import re
from contextlib import ExitStack
from enum import Enum
from typing import Any, Dict, List, Optional
from airflow.models import BaseOperator
from airflow.providers.google.cloud.hooks.dataflow import DEFAULT_DATAFLOW_LOCATION, DataflowHook
from airflow.providers.google.cloud.hooks.gcs import GCSHook
from airflow.utils.decorators import apply_defaults
from airflow.version import version
class CheckJobRunning(Enum):
    """
    Helper enum for choosing what to do if job is already running
    IgnoreJob - do not check if running
    FinishIfRunning - finish current dag run with no action
    WaitForRun - wait for job to finish and then continue with new job
    """
    IgnoreJob = 1
    FinishIfRunning = 2
    WaitForRun = 3
class DataflowCreateJavaJobOperator(BaseOperator):