[PLT-1437] Restore client.headers

[vbrodsky]

Description

Restored back client.headers that we have lost as a result of transition to Client to use http connection pool

Tested with the following script using qa staging org:

import urllib.request

from PIL import Image

from val_scripts.utils import TestClient

# import logging
# logging.basicConfig()
# logging.getLogger().setLevel(logging.DEBUG)

client = TestClient.stg_client()

# === Create data rows ====
org = client.get_organization()
user = client.get_user()
print("Org ", org.uid)
print("User ", user.uid)

composite_mask_url = "https://api.lb-stage.xyz/api/v1/tasks/cm0csqagl00er07yada9qfsd3/masks/clktt4l0j000d3b6qdu7pttqd/index/1"
mask_url = "https://api.lb-stage.xyz/api/v1/projects/clktt2fbx01gf07170ofxfskl/annotations/clktt4lky000f3b6qwsv6stor/index/1/mask"

def download_image(mask_url, client):

    import pdb; pdb.set_trace()
    req = urllib.request.Request(mask_url, headers=client.headers)

    # Optionally, print the image of the mask
    image = Image.open(urllib.request.urlopen(req))
    image.show()


def export_project(project_id: str, client: TestClient):
    params = {
        "data_row_details": True,
        "metadata_fields": True,
        "attachments": True,
        "project_details": True,
        "performance_details": True,
        "label_details": True,
        "interpolated_frames": True}

    project = client.get_project(project_id)
    export_task = project.export_v2(params=params)

    export_task.wait_till_done()
    if export_task.errors:
        print(export_task.errors)
    export_json = export_task.result
    print(export_json)


# export_project('clktt2fbx01gf07170ofxfskl', client)
download_image(mask_url, client)

Fixes # (issue)

Type of change

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• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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